Topic: Decimal fractions. Reading and writing decimals.
Goals:
1. Formation of knowledge and skills to write and read decimals. Introduce students to new numbers - decimals (a new way of writing numbers)
2. Develop a culture of mathematical thinking, intuition, conjecture, erudition and mastery of mathematical methods.
3. Arouse mathematical curiosity and initiative, develop a sustainable interest in mathematics.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
I'm glad to see you. We are starting our lesson. Today in the lesson you will learn that we need knowledge of mathematics in real life. I want this lesson to bring you new discoveries, and I hope that you will successfully apply your existing knowledge to solve practical problems. I invite you to guess the word I have in mind, which will be the key word of our lesson. You have three tries. The dictionary says about it like this:
– these are small lead balls for shooting from a hunting rifle;
– these are frequent intermittent sounds, for example “drum…”;
– it can be regular or irregular, ordinary or decimal.
(This word is “Fraction”.)
As R. Descartes said: “The curious seeks out rarities only to be surprised by them; inquisitive in order to recognize them and stop being surprised.” So let's be inquisitive!
Write the numbers as a sum of digit terms.
2973=2000+900+70+3
Write the amount as one number:
8000 + 700 + 20+9=
Remember that the unit of each subsequent digit is 10 times greater than the unit of the previous digit. If there is no digit, then in the number record we put 0 in its place.
Work in groups:
1 group: Present in meters:
7 dm = 28 cm = 4 cm =
2nd group: Present in centners:
4 kg = 23 kg = 5 g = 78 g =
Group 3: Present in hours:
20 min = 3 min = 17 sec =
Additional task: Present in hryvnia:
4 kopecks = 13 kopecks = 38 kopecks =
Pay attention to the denominators of the resulting fractions. Do you agree that in the tasks the denominators are numbers written by ones and zeros, i.e. 10, 100, 1000, etc.? with such fractions, as can be seen, one often has to deal with everyday life, perform calculations on them. Therefore, to write fractions whose denominators are 10, 100, 1000, etc., they use the positional principle of representing numbers in the decimal number system and call them decimal.
The invention of decimal fractions is one of the greatest achievements of human culture. The rules for calculations with decimal fractions were described by the famous medieval scientist al-Kashi Jemshid Ibn Masud, who worked in Uzbekistan, near the city of Samarkand at the Ulegbek Observatory at the beginning of the 15th century. Al-Kashi wrote fractions on the same line with numbers in the decimal system, to separate the whole from the decimal, he used a vertical line or ink of different colors. His works were not known to European scientists for a long time, and only 150 years later were decimal fractions reinvented.
The new type of fractions is simpler and more convenient, which we will get acquainted with today.
Decimal fraction,
So great.
Ordinary sister, -
Its denominator is
You need to know the places of tenths.
Questions:
1. What is the smallest digit for natural numbers? (unit digit)
2. Can there be an even smaller discharge? (yes, if you use fractions)
3. How many times do you think the digit that we place in the first place to the right of the units digit can be smaller? (10 times)
We call this category tenths of units. Question:
The digit following the tenths digit, how many times do you think will be less than one? (100 times)
Questions:
1. What would you call the next category? (thousandths of units)
We have every reason to write and read decimals. But remember that we will write the digits of the fractions to the right of the digit of the units. A comma is placed between the whole and fractional parts. If there is no fractional digit, we replace it with 0 when writing the number.
For example: 4=4,1, , 2.
If we have a proper fraction, then in place of the whole number we write 0.
For example: , , .
Please note that the number of digits after the decimal point is equal to the number of zeros that come after the one in the denominator.
1) Write in decimal fraction:
A) 2.7; 11.4; 401.1; 0.8; 99.9; 909.9.
B) 5.64; 21.87; 381, 77; 54.60; 0.55; 0.09; 2.02.
B) 1.597; 12.882; 326.703; 0.321; 0.049; 0.001.
D) 203.6; 20.36; 0.0236; 2.0306; 0.010101.
3) Write down decimal fractions from dictation.
· 7 point 8
· 2 point 25 hundredths
· 0 point 92 hundredths
· 12 point 3 hundredths
· 5 point 187 thousandths
· 24 whole 24 thousandths
· 7 point 7
· 7 point 7 hundredths
· 7 point 7 thousandths
· 0 point 5 ten thousandths
· 2 point 2 thousand 35 millionths
· Solve orally No. 000, 777, 773.
6. Historical background
The concept of an abstract decimal fraction first appeared in the 15th century. It was introduced by the eminent mathematician and astronomer Al-Cauchy ( full name Jemiad ibn – Masud al – Qoshi) in the work “The Key to Arithmetic” (1427). Al-Cauchy's discovery in Europe became known only 300 years later.
Knowing nothing about Al-Cauchy’s discovery, decimal fractions were discovered for the second time, approximately 150 years after him, by the Flemish mathematician and engineer Simon Stevin in his work “Decimal” (1585).
In Russia, the doctrine of decimal fractions was first presented in his “Arithmetic” - the first Russian textbook mathematics. (1703 g)
It was proposed in different ways to separate the whole part from the fractional part. Al-Koshi wrote the whole and fractional parts in one row, although he wrote them in different inks, or put a vertical line between them. To separate the whole part from the fractional part, S. Stevin put a zero in the circle. The comma adopted in our time was proposed by the German astronomer J. Kepler (1571 - 1630).
7. Independent work.
Solve No. 000.
8. Summing up the lesson.
Reflection.
What new things have you learned?
What did you find difficult?
What have you learned?
Did we manage to solve it?
· Gained good knowledge.
· Mastered all the material.
· Partially mastered the material.
9. Homework.
Learn paragraph 27.
Repeat step 2.
solve No. 000, 778, 774.
Creative task: message “From the history of decimal fractions.”
But about how important accuracy is in calculations, listen to an excerpt from the poem “Three Tenths”
Three tenths... Tell me about such a mistake,
And, perhaps, you will see a smile on their faces.
Three tenths... And yet about this mistake
I ask you to listen to me without smiling.
If, while building your house, the one in which you live,
The architect made a slight mistake in his calculations -
What would happen, do you know, Kostya Zhigalin?
This house would turn into a heap of ruins!
You step on the bridge, it is reliable and strong,
If the engineer weren’t precise in his drawings,
If you, Kostya, fell into a cold river,
I wouldn't say thank you to that person!
Here is a turbine, its shaft has been bored out by turners.
If the turner were not very precise in his work,
Kostya, a great misfortune would happen,
It would blow the turbine into small pieces.
Three tenths - and the walls are erected askew!
Three tenths - and the cars will fall off the slope!
Make a mistake by only three tenths - pharmacy -
The medicine will become poison and kill a person...
Objective of the lesson:
· create conditions for deriving the rule for comparing decimal fractions and the ability to apply it; repeat the recording of ordinary fractions in the form of decimals;
· develop logical thinking, ability to generalize, research skills, speech;
· cultivate compliance with norms of behavior in a team, skills of joint activities when working in groups, and the ability to give reasons for one’s actions.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
Problem solving is a practical art, like swimming, skiing or playing the piano, that can be learned. “If you want to swim, go into the water, and if you want to learn how to solve problems, then solve them,” famous American mathematician George Polya advised students in his book “How to Solve a Problem.” Solving any fairly difficult problem requires hard work, cultivates will, perseverance, develops curiosity and ingenuity. These are very necessary qualities in a person’s life, because even the proverb says: “a mind without a guess is not worth a penny.”
Today we have a lesson on the topic “Comparing decimals.”
3. Updating of basic knowledge.
1. Read the fractions:
17,3; 0,07; 53,2; 1,251; 0,26; 7,1027;
2,7; 0,127; 0,1; 0,34; 2,141; 0,0537;
2. In each fraction, move the comma one place to the left. Read
received numbers:
34,1; 310,2; 110,1; 105,007; 2,7; 3,4;
3. In each fraction, move the comma one place to the right. Read
received numbers:
1,37; 0,1401; 3,017; 1,7; 37,4; 350,4.
Solve No. 000, 779.
Compare natural numbers:
Solve No. 000, 790.
Repeat the rule for comparing natural numbers.
4. Studying new material.
Task: compare the numbers (written on the board)
18.625 and 5.784 15.200 and 15.200
3.0251 and 21.02 7.65 and 7.8
23.0521 and 0.0521 0.089 and 0.0081
First we open the left side. Whole parts are different. We draw a conclusion about comparing decimal fractions with different integer parts. Open the right side. Whole parts are equal numbers. How to compare?
I wrote out the rule for comparing decimal fractions that the author suggests. Let's compare.
- Rule for comparing decimal fractions
If the whole parts of decimal fractions are different, then the fraction with the larger whole part is greater.
If the whole parts of decimal fractions are equal, then the fraction with more tenths is greater.
If there are equal numbers of tenths, then the fraction that has more hundredths is larger, etc.
You and I have made a discovery. And this discovery is the rule for comparing decimal fractions. It coincided with the rule proposed by the author of the textbook.
If you add a zero or discard the zero at the end of a decimal fraction, you get a fraction equal to the given one.
For example,
0,87 = 0,870 = 0,8700; 141 = 141,0 = 141,00 = 141,000;
26,000 = 26,00 = 26,0 = 26; 60,00 = 60,0 = 60;
0,900 = 0,90 = 0,9.
Let's compare two decimal fractions 5.345 and 5.36. Let's equalize the number of decimal places by adding a zero to the right of the number 5.36. We get the fractions 5.345 and 5.360.
Find equal fractions:
0,89; 1,700; 0,30000; 1,7; 1,0000; 3,0; 2,3; 2,300; 1,00; 2,30; 0,3; 1,00000; 0,300; 0,03.
By adding zeros to the right, equalize the number of decimal places in decimal fractions:
1.8; 13.54 and 0.789.
Write the fractions in short:
2,5000; 3,02000; 20,010.
5. Understanding new material.
Task: compare
Work in pairs.
3.4208 and 3.4028
So what did we learn to do today? Let's check ourselves. Students compare decimal fractions using >,<, =.
Independent work.
(Check - answers on the back of the board.)
Compare:
148.05 and 14.805
6.44806 and 6.44863
35.601 and 35.6010
What interesting things did you notice? Were there any lungs among them?
Some numbers could be compared using the whole number, while others had to be compared using the fractional part.
Which ones were more interesting to compare? Why?
23,43 < 23,9. Там целые равны, а в дробной части, если не знать правило, можно сравнить как 9 и 43, и можно допустить ошибку.
Solve No. 000, 794, 795, 797.
6. Physical education minute.
We're a little tired
Let's rest for a minute.
Turn, tilt, jump,
Smile, come on, buddy.
Jump again: one, two, three!
Look at your neighbor
Hands up and then down
And sit down at your desk again.
We have become more cheerful now,
Let's think faster.
7. Independent work.
Work in pairs.
Replace the “*” with a number so that the resulting entry is correct:
1) 5,688 < 5,6*1;
2) 71,09* < 71,091;
3) 9,*57 > 9,499;
4) 0,7*5 < 0,725;
5) 5*,67 < 52,31;
6) 3,*2 < 3,93.
8. Lesson summary. Reflection.
Learn paragraph 28.
Solve No. 000, 798, 800.
Students fill out cards.
Card__________________________________________________
I, ____________ (name), learned in class today
(what to do)__________________________________________
You need to act according to the following algorithm:
If _____________ parts of decimal fractions are unequal, then__________________________________________
Example:_________________
If _____________ parts of decimal fractions are equal,
then you need (what to do) ________________________________decimal places.
Compare (what)__________________________________________
And________________________________________________________
Example:___________________
Topic: Comparing decimals.
Objective of the lesson:
· To consolidate the rules for comparing decimal fractions and the ability to apply them; repeat the recording of ordinary fractions in the form of decimals;
· develop logical thinking, ability to generalize, research skills, speech.
· cultivate compliance with norms of behavior in a team, skills of joint activities when working in groups, and the ability to give reasons for one’s actions.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
The motto of the lesson: “Have excellent knowledge on the topic of decimal fractions.”
One, two, three, four, five
And as soon as we grow up
We are all going to study.
Multiply, add
We also count fractions
How else? It is forbidden?
Mathematics is
Everyone in the world needs
You go to the store, to the bank
Otherwise you'll go broke
You will cry.
One student from each team goes to the board on which columns of six pairs of decimal fractions are written. The guys should put up a sign< ; >or =.
What is the shortest way to write fractions whose denominator is one with several zeros?
What is this type of fraction notation called?
Write as decimals:
Solve No. 000.
4. Solving exercises on comparing decimal fractions.
Solve No. 000, 805, 807, 809.
5. Independent work.
|
Ioption 1) Compare numbers: a) 3.61 and 1.69 b) 0.034 and 0.035 d) 0.6 and 0.600 2) Write in ascending order: 8,02; 9,4; 8,2; 8,22. a) 2,*1< 2,02 b) 0.39826< 0,3*845 c) 1.892< 1,*0765 4) Place the right sign < или >: a) **.412 and *.9* b) 0.742 and 0.741** 2 < x < 2,0001 Additionally: 6) Compare the values: a) 6.7 m and 6690 mm b) 83.62 c and 8.362 t. |
IIoption 1) Compare numbers: a) 8.57 and 4.56 c) 0.957 and 0.964 d) 0.90 and 0.900 2) Write down the numbers in descending order: 4,5; 5,72; 4,05; 4,55. 3) Substitute a number instead of an asterisk so that the correct inequality is formed: a) 6.413 > 6.4*8 b) 4.5*8 > 4.593 c) 5*.683< 50,6*1 4) Place the desired sign< или >: a) 4.3** and 4.7** b) *,*** and **,**. 5) Find 2 values of x for which the inequality is true: 1,999 < x < 2 Additionally: 6) Compare the values: a) 18.34 kg and 243.6 g b) 7.3 dm and 8.6 cm. |
6. Logical task.
Five chickens weighed different breeds: white, gray, black, red and motley. We got the following results: 0.3 kg; 0.52 kg; 0.16 kg; 0.88 kg; 0.28 kg. It is known that the red chicken is lighter than the gray one, but heavier than the white one. The black one is heavier than the motley chicken, and the motley one is heavier than the gray one. How much does each chicken weigh?
7. Summing up the lesson. D/z.
1.Who can formulate the name of the lesson topic?
2. What new did you learn in the lesson? What skills did you acquire?
Solve No. 7b. - 802, 804, 11 b, 810
Lesson objectives:
· repeat previously studied material, teach children to round decimal fractions;
· develop mathematical speech, attention,
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
3. Updating of basic knowledge. Checking d/z.
1. Indicate which numbers are equal to 2.034.
A) 2.34; B) 2.03; B) 2.0340; D) 2.03400.
2. Arrange the numbers 4,28; 3.289; 4.249; 3.78 ascending.
A) 4.28; 4.249; 3.78; 3.289;
B) 3.289; 3.78; 4.249; 4.28;
B) 4.249; 4.28; 3.289; 3.78;
D) 3.78; 3.289; 4.28; 4.249.
3. What number can be used to replace X in inequality 0.03< X< 0,031, чтобы оно было верным?
A) 0.030; B) 0.0301; B) 0.0309; D) there is no such number.
4. Indicate those inequalities that are true when replacing an asterisk with any number other than 0.
A) 67.28*>67; B) 75.62*<75,629* В) 564,2*7>564.27 G) *,**>**,*
5. Indicate all the numbers that can be put instead of * so that the entry is 0.7*5<0,*62 выражала верное неравенство А) 0; Б) 8, 9; В) 9; Г) 1, 2, 3, 4, 5, 6.
Remember the rules for rounding natural numbers and round these numbers:
a) up to thousands:; ;;
b) up to millions:; ; 008
Solve No. 000 (1, 2) – independently.
4. Studying new material.
When rounding decimal fractions, use the same rules as when rounding natural numbers.
· To round a number to the specified digit, you need to:
· Separate all numbers after this digit;
· Underline the first of those numbers that are separated, and determine which numbers include: 0; 1; 2; 3; 4 or 5; 6; 7; 8; 9 she is located;
· If the number 0 is underlined; 1; 2; 3; 4, then all numbers that are separated are replaced with zeros; if the number 5 is underlined; 6; 7; 8; 9, then 1 is added to the digit to which rounding is carried out, and all digits that are separated are replaced with zeros;
· In the answer, all zeros in the fractional part of the decimal fraction that are to the right of the digit to which rounding is carried out are discarded.
5. Understanding new material.
Solve No. 000, 820 (a), 823.
To what digit is rounding done?
6. Relaxation.
Eyelashes droop...
Eyes are closing...
We are resting peacefully... (twice).
We fall asleep in a magical sleep...
Breathe easily... evenly... deeply...
Our hands are resting...
They rest, fall asleep... (twice).
The neck is not tense...
The lips part slightly...
Everything is wonderfully relaxed... (twice).
Breathe easily... evenly... deeply.
7. Independent work.
Solve No. 000.
A student works on a hidden board. Then check.
8. Lesson summary. Reflection.
Learn item 29.
Solve No. 7 b. – 819, 11 b. –825, 827.
1) What topic was discussed in class today?
2) What rules did we repeat today?
3) What other operations can be done with decimal fractions?
4) What do you think the topic of the lesson will be tomorrow?
Topic: Rounding decimals.
Lesson objectives:
· Consolidation of skills in comparing and rounding decimal fractions;
· develop a culture of oral and written mathematical speech,
attention,
· cultivate neatness, interest in the subject, activity, perseverance.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
3. Updating of basic knowledge. Checking d/z.
1. What types of numbers do you know?
2. What numbers are called natural numbers?
3. Is zero a natural number?
4. What numbers are called decimal fractions?
5. What decimal places do you know?
6. What can you do with decimals?
7. Formulate a rule for comparing decimal fractions.
8. Formulate a rule for rounding decimal fractions.
Arrange the numbers in the table in ascending order.
0,08; 0,29; 0,3; 1,48; 1,5; 2,06; 2,1; 5,39; 5,4.
Work in pairs.
Decimal fractions and their rounding are given. Find a match and indicate to what digit the rounding was performed:
0,320,3 25,18625,2 183,809
19,027319,027 37,195137,195 81,258781,26
193,76021 193,7,30507125,3051 83,620983,62
4. Solving exercises on rounding and comparing decimals.
Solve No. 000 (b, c), 826, 779.
5. Physical education minute.
You are overcome by drowsiness,
Reluctant to move?
Come on, do it with me
The exercise is like this:
Stretch up, down,
(Hands up, stretched.)
Wake up completely.
Extend your arms wider.
(Hands to the sides.)
One, two, three, four.
Bend over - three, four
(Bends the body.)
And jump on the spot.
(Jumping in place.)
On the toe, then on the heel.
We all do exercises.
6. Independent work.
Option 1
a) 0.35*70.352;
b) 16.11416.1*;
c) 25.8*125.84;
e) 23.*75623.9.
Option 2
Substitute a number instead of * to make the equality true:
a) 14.22514.2*;
c) 57.5*557.58;
d) 20.*91620.5;
7. Lesson summary. D/z.
- Solve No. 000, 824, 780. Repeat step 6.
Now I will tell you a parable.
A sage was walking, and three people met him, carrying carts with stones for construction under the hot sun. The sage stopped and asked each one a question. The first one asked: “What have you been doing all day?” And he answered with a grin that he had been carrying the damned stones all day. The sage asked the second: “What did you do all day?”, and he answered: “And I did my job conscientiously.” And the third smiled, his face lit up with joy and pleasure: “And I took part in the construction of the temple!”
Guys! Let's try to evaluate everyone's work for the lesson.
Those who worked like the first person raise blue squares.
Those who worked conscientiously raise green squares.
Those who took part in the construction of the Temple of Knowledge raise red squares.
Subject: .
Lesson objectives:
educational:
developing:
educational:
Progress of the lesson.
1. Organizational moment.
Good afternoon
They sat up straight and looked around.
Smiled at each other
And they plunged into work.
2. Lesson motivation.
Decimal fractions - new to you
Only recently did your class recognize them
There’s just more hassle for everyone now
We teach, we learn the rules, we prepare for the lesson.
3. Updating of basic knowledge. Checking d/z.
Blitz survey (fill in the blanks):
Common fractions with numbers in the denominator 10,100, 1000 , etc., are written in short without a denominator.
Separates the integer part from the fractional part comma.
Writing a fraction using a comma to separate the whole part from the fractional part is called decimal notation fractional number.
In the decimal fraction, before the decimal point, write whole part, and after the decimal point - fractional part.
If the common fraction is proper, then in decimal notation we write the number before the decimal point 0 .
In a decimal fraction, after the decimal point, from left to right, the following digits follow:
Tenths
Hundredths
thousandths
ten thousandths
hundred thousandths
Millions
To compare two decimal fractions, you need …
To round a decimal fraction, you need …
Fill in the blank...
Lake Baikal is the deepest place on the globe. Its depth reaches 1622 m or 1,622 km
The deepest place in the world's oceans is recorded in the Pacific Ocean near the Mariana Islands. It will be in kilometers 11,022 km
The Siberian sturgeon is one of the large fish. Its length reaches 3 m, ( 0,003 km) weight more than 100 kg ( 0,1 T).
The highest continent on earth is Antarctica. Its average height is 2040 m above sea level. ( 2,04 km) The only inhabitants are scientists and researchers of this continent.
The longest animal - a tapeworm - was found in the coastal waters of the South Sea. Its length was 54 m 90 cm. ( 54,9 m)
4. Studying new material.
To add (subtract) decimal fractions, you need:
1) Equalize the number of decimal places in these fractions;
2) Write them below each other so that the comma is written under the comma;
3) Perform addition (subtraction) without paying attention to the comma;
4) Place a comma under the comma in the given fractions in your answer.
5. Consolidation of new material.
Solve No. 000, 835, 837.
6. From the history of mathematics:
The rules for calculations with decimal fractions were described by the famous scientist al-Kashi Jemshid Ibn Masud at the beginning of the 15th century. He wrote fractions in the same way as is customary now, but did not use a comma: he wrote the fractional part in red ink or separated it with a vertical line. But in Europe they did not find out about this, and only 150 years later the scientist Simon Stephen wrote down decimal fractions in a rather complicated way: instead of a decimal point, a zero in a circle. A comma or period to separate a whole part has been used since the 17th century. In Russia, he outlined decimal fractions in 1703 in the first mathematics textbook “Arithmetic, that is, the science of numerals.”
7. Logical task.
Work in pairs. Restore the commas in the examples:
8. Lesson summary. D/z.
1. What new did you learn, what did you learn, what did you remember, what did you repeat?….
2. Whose answers did you like best?
3. What will you remember for a long time after today’s lesson?
4. Your impressions of the lesson. Emotional mood.
To your home:
Learn paragraph 30.
Solve No. 8 b. - No. 000, 836, 11b. - No. 000,
Come up with and beautifully arrange on a landscape sheet a task that would be
solved using addition and subtraction of decimal fractions, write down the condition on a piece of paper
problem and draw a picture based on this condition, and write down its solution in a notebook.
Try to ensure that the students in the class like your task so that the data in the condition
corresponded to reality.
To add decimal fractions,
We don't have to think twice about it:
Let's line up all the commas in a row,
The number under the number strictly stands.
And as a result we will get again,
More than others, a decimal fraction.
Or this algorithm:
Subtract decimals, add them,
Strictly write the number below the number,
And keep all the commas,
Write them in a row, don’t forget!
Subject: Adding and subtracting decimals .
Lesson objectives:
educational: developing knowledge about the algorithm for adding and subtracting decimal fractions;
developing: develop logical thinking, memory, cognitive interest;
continue the formation of mathematical speech; develop the ability to analyze and compare, draw analogies;
educational: development of curiosity and interest in the subject; improving the skills of aesthetic design of notes in a notebook.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
3. Updating of basic knowledge. Checking d/z.
Rule for adding and subtracting decimals.
a) Write the signs “+” or “–” in the circles so that the equations are true.
0.5 O 2.7 O 0.2 = 3; 7.4 O (12.3 O 9.2) = 4.3.
b) Between the numbers 5.2 and 5.3, put a number greater than 5.2 and less than 5.3.
c) How to quickly and easily find the sum of these amounts 2.18 + 4.36 + 6.53 + 8.77 and
7,82+5,64+3,47+1,23
Follow the steps below:
4. Solving exercises on adding and subtracting decimals.
Solve No. 000, 839, 841,
5. Physical education minute.
Breathe deeply through your nose
Breathe deeply through your nose
We get up easily.
(Squats.)
We lean forward.
We bend back.
Like the wind bends trees.
So we sway in harmony
(Bends back and forth.)
Now let's turn our heads -
That's how we'll think better.
Twist and turn
And then vice versa.
(Rotate your head to the sides.)
Let's stand, children, on our toes -
(Stretching - arms up.)
We put an end to charging.
6. Independent testing work
|
Ioption |
IIoption |
||
|
1. Find the amount |
|||
|
2) 25,49 + 0,375 3) 0,0374 + 49,9626 |
2) 0,598 + 32,24 3) 29,9738 + 0,0262 | ||
|
2. Perform subtraction: |
|||
|
1) 2,56 – 0,468 3) 0,4008 – 0,243 |
1) 7,82 – 0,746 3) 0,3007 – 0,189 | ||
7. Summing up the lesson. D/z.
Reflection.
What new things have you learned?
What did you find difficult?
What have you learned?
What problem was posed in class?
Did we manage to solve it?
Write how you learned the lesson material on the feedback sheets.
· Gained good knowledge.
· Mastered all the material.
· Partially mastered the material.
Solve No. 000,
Lesson topic: “Adding and subtracting decimals.”
Lesson objectives:
1. Systematize the material on the topic “Adding and subtracting decimals.” Enrich knowledge, establish connections between theory and practice.
2.Develop computing skills, memory, thinking and ingenuity.
3.Cultivate cognitive interest in the subject.
Progress of the lesson.
1. Organizational moment.
2. Lesson motivation.
“It is not enough to acquire wisdom,
You also need to know how to use it.”
Cicero
Discuss the statement with students.
Conclusion: it is not enough to know the rules, you must be able to apply them.
3. Updating of basic knowledge. Checking d/z.
Why do we need decimals? Maybe it could have been done
natural numbers and ordinary fractions?
The notation is convenient; operations with decimal fractions are similar to those with
natural numbers that we know well can be counted using
calculator.
It is known how important the comma is in the Russian language. From the wrong
By placing commas, the meaning of a sentence can change dramatically. For example, "Execute"
You can’t have mercy” and “You can’t execute, you can have mercy.” In mathematics, from the position of the decimal point
Whether the equation is true or false depends.
Arrange commas to form correct equalities.
0,42 + 1,7 = 2,12
7,36 – 3,36 = 4
63 – 2,7 = 60,3
4. Solution of exercises.
1. Give examples where addition is done correctly.
A) 279.04 B) 37.284 c) 28.145 d) 42.790
0,28 + 221,37 +454,37 + 0,284
279,32 59,82 43,074
2. Enter the value of the sum 42.7 + 0.56.
A) 48.3; B) 43.26; B) 4.83; D) 44.26.
3. Enter the difference value 34.7 - 2.729.
A) 32.071; B) 7.41; B) 3.1971; D) 31.971.
4. Specify the value of the expression,08 + 8.5 + 6.24.
A) 21.76; B) 22.66; B) 15.01; D) 23.66.
5. The root of the equation 2.73 - x = 0.219 is the number:
A) 2.511; B) 2.949; B) 0.074; D) 2.611.
6.A boat is moving along the river at a speed of 28.7 km/h. Current speed is 3.1 km/h. Indicate true statements about the movement of the boat.
A) The speed of the boat in still water is 31.8 km/h.
B) The speed of the boat against the current is 22.5 km/h.
B) A boat moves faster against the current than in still water.
D) In still water, the speed of the boat is 25.6 km/h.
7. What number should be put in the equality 19.7+*,* = 2*.5 instead of an asterisk for it to be correct?
Solve No. 000, 856 (1, 2), 858 (2, 3),
5. Independent work
( work in pairs, repeat the rules for adding and subtracting decimal fractions, followed by verification).
Find the missing number:
1. _______ +3,015 = 3,605
2. 21,035 - ________ =11,3
3. 106,314+________=120,404
4. 0,35+10,7+16,05 =________
5. (18,325+10,7) - ________=0,375
6. Logical pause.
The proverb says: “A mind without a guess is not worth a penny.”
Solving any fairly difficult problem requires hard work,
fosters will, perseverance, develops curiosity and ingenuity. These are very important
quality in human life.
1. Two amounts are given:
7.82 + 5.64 + 3.47 + 1.23 and 2.18 + 4.36 + 6.53 + 8.77
Find the sum of these amounts. Answer: 40.
2. Find the meaning of the expression:
(0.5 – ½) (13 – 2.46 – 3.54). Answer: 0.
3. Calculate in the simplest way:
5.94 * 2.67 + 0.33 * 5.94 + 3* 0.06. Answer: 18.
7. Summing up the lesson.
Reflection.
What new things have you learned?
What did you find difficult?
What have you learned?
8. Homework.
Repeat step 7. Solve for 7 points. - No., 11 b. – 844,
Lesson topic: Generalization and systematization of knowledge and skills on the topic “Adding and subtracting decimal fractions.”
Goals:
1. Generalization and systematization of students’ knowledge on the topic “Adding and subtracting decimals”, consolidating the skills and abilities of applying the rules of comparisons, rounding, adding and subtracting decimals when solving problems;
2. To develop students’ logical thinking, students’ cognitive activity, and independence.
3. To cultivate accuracy and attentiveness in students, a culture of writing, interest in the subject, erudition, and perseverance.
Progress of the lesson.
1. Organizational moment.
Emotional mood.
How are you living? (children respond with gestures and movements)
How are you going?
How are you running?
Do you sleep at night?
How do you give?
How do you take it?
How are you being naughty?
How are you threatening?
How are you sitting?
How do you know mathematics?
2. Lesson motivation.
Today our lesson is called a public review of knowledge on the topic “Decimals”. And today each of you must report on the material you have studied. The results will be entered into the evaluation sheet.
So, let's take a trip around the city of "Decimal Fractions".
Today in class
We will go to the Palace of Mathematics for knowledge.
Let's take our ingenuity and imagination with us.
We will not turn off the road anywhere.
But in order for us to achieve our goals as quickly as possible,
We must rise
Up the stairs.
3. Updating of basic knowledge. Checking d/z.
To enter this city you must answer the following questions:
Student survey: “You - for me, I - for you” (for each correct answer, the student receives 1 point)
1. What is a decimal?
2. What does a decimal fraction consist of?
3. What are the names of the digits of the decimal fraction to the right of the decimal point?
4. By what principle are decimal fractions written?
5. How to write a decimal fraction as a mixed number?
6. Formulate a rule for comparing decimal fractions?
7. Formulate the rule for rounding decimal fractions?
8. What does it mean to round a decimal to the nearest tenth? hundredths?
9. How to add decimals?
10. How to subtract decimals?
Giant
They stood at their desks.
1 exercise. (the correct solution is to clap above your head, the wrong solution is to spread your arms to the sides.)
3,7- 0,3 = 3,4 5,6 + 3,8 = 8,14
5,6 + 3,8 = 9,4 2,8 +0,3 = 0,33
Exercise 2. (the correct root is tilting the heads forward, the incorrect root is tilting the head to the left and right.)
X+2.7=6.9,X=4.2X=9.6
U-5.3=1.1;U=4.2;U=6.4.
The next street is “Computational”.
Solve No. 868.
1 point for a correct example. Maximum -6 points.
In the empty cells of the square, write numbers such that the sum of the numbers along any horizontal, vertical and diagonal is equal to 3.
Work in pairs.
Maximum -4 points.
Checkout Square.
Option 1.
1. Which of these numbers is the largest:
a) 1.98 b) 0.98 c) 1.03 d) 0.08?
19,9 * 4 < 19,941?
k) 5 m) 0 c) any d) other answer
3.Add: 4.12 + 5.51
o) 9.62 u)9.53 b)9.63 h) another answer
4. Subtract: 3.61 – 2.51
j) 1.1 b) 1.11 c) 0.1 p) another answer
5.Solve the equation: x+3.4 = 7.6
a) 4.2 b) 11 c) 4.1 d) another answer
6.Round the number: 10.856 to the nearest hundredth
a) 10.9 w) 10.86 g) 11.8 x) another answer
7.Which of these decimal fractions is located on the coordinate ray to the right:
a) 1.7 i)2.24 c)1.8 d)0.22
Option 2.
1. Which of these numbers is the smallest:
a) 0.0687 b) 0.075 c) 0.306 d) 2.457?
2.What number can be substituted for the asterisk to get the correct inequality:
27, * 376 <27,2299?
k) 2 m) 0 or 1 c) any d) another answer
3.Add: 4.1 + 2.51
o) 2.92 u) 6.52 b) 6.61 h) another answer
4. Subtract: 13.1 – 2.51
j) 11.59 b) 10.5 c) 11.5 p) another answer
5.Solve the equation: x-1.9 = 6.39
a) 8.29 b) 4.49 c) 7.29 d) another answer
6.Round the number: 15.9476 to the nearest hundredth
a) 15.94 w) 15.95 g) 15.9 x) another answer
7.Which of these decimal fractions is located on the coordinate ray to the left:
a) 1.75 i) 1.7489 c) 2.24 d) 2.2499
Then - mutual verification. Maximum -7 points.
5. Summing up the lesson.
Assessment. Divide the sum of points by 2.
Answer the questions:
- What knowledge did you need in the lesson? What did you like most about the lesson? Where did you do well during the lesson? What words can you use to express your mood as a result of your work in class?
Solve No. 000,
Topic: Test on the topic “Adding and subtracting decimals”.
Goals:
1. Test students’ knowledge, skills and abilities on the topic “Adding and subtracting decimals.”
2. Develop attention, logical thinking, written mathematical speech;
3. Foster independence and hard work.
Lesson progress
1. Organizational moment.
2.Lesson motivation.
3. Test (see in the section “To help the teacher”)
4. Lesson summary.
Repeat p.
Goals: 1.Formation of cognitive competencies;
2. Develop attention, the ability to think outside the box, memory, and the formation of communicative competence;
3.Build social competence.
Lesson progress
1. Organizational moment.
2.Lesson motivation.
3. Summing up the results of the case.
Analysis of common mistakes at the board.
4. Individual work on mistakes.
5. Lesson summary
Repeat steps 27 – 30. Solve No. 000, 860.
Subject:
Target: introduce students to new numbers - decimal fractions, build knowledge and
Lesson type:
Equipment:
tasks.
View document contents
"Lesson summary on the topic "The concept of a decimal fraction. Reading and writing decimal fractions.""
Subject: The concept of a decimal fraction. Reading and writing decimals.
Target: introduce students to new numbers - decimal fractions, build knowledge and
mastery of mathematics methods; cultivate a culture of mathematical thinking.
Lesson type: lesson of learning new material.
Equipment: teacher's computer, screen, multimedia projector; on the tables: sheets with
tasks.
Lesson structure:
Organizational moment.
Guys, today in class you must discover new knowledge, but, as you know, every new knowledge is related to what we have already learned. So let's start with a review.
Preparing to study new material.
Solve the anagram: fraction, angle, numerator, denominator.
Read the numbers in the table of digits.
From the numbers given, choose: natural numbers, proper fractions, improper fractions, mixed numbers.
Familiarization with new material.
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| Our lesson will be dedicated to The topic of the lesson is “The concept of a decimal fraction. Reading and writing decimals." Lesson motto: Have excellent knowledge on the topic “Decimal Fractions.” |
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| Let's remember how the decimal number system works. Let's look at the table of categories and answer the questions: Questions: Read the numbers written in the table. How does the position of the unit change in each subsequent line compared to the previous one? How does the value of the corresponding number change? What arithmetic operation corresponds to this change? Conclusion : moving the unit one digit to the right, each time we decreased the corresponding number by 10 times and did this until we reached the last digit - the units digit. Is it possible to reduce one by 10 times? Problem: But there is no place for this number in our table of digits yet. Think about how you need to change the table of digits so that you can write the number in it. |
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| We reason that we need to move the number 1 to the right by one place. But there are no digits to the right of the units digit, which means we need to add another column. Come up with a name for this column: tenths. Reasoning similarly: (hundredths) and: 10t. = (thousandths), etc. |
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| Since we reasoned correctly, we get the following table: |
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| 2 units 3 tenths. And in order to write numbers outside the table, we need to separate the whole part from the fractional part with some sign. We agreed to do this using a comma or period. In our country, as a rule, a comma is used, and in the USA and some other countries, a period is used. We read the numbers as follows: a) 2,3 or 2.3 (two point three or two, comma, three or two, point, three) |
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| You and I have made a discovery. And this discovery is the rule for reading and writing decimal fractions. It coincided with the rule proposed by the author of the textbook. Rule: If a comma (or period) is used in the decimal notation of a number, then the number is said to be written as a decimal fraction. For brevity, numbers are simply called decimals. |
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| In science and industry, in agriculture, decimal fractions are used much more often than ordinary fractions. This is due to the simplicity of the rules for calculations with decimal fractions and their similarity to the rules for operations with natural numbers. 1703 - In Russia, the doctrine of decimal fractions was presented by Leonty Filippovich Magnitsky in the textbook “Arithmetic, that is, the science of numerals.” |
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| We have every reason to complete tasks on the topic of the lesson. First task. Read the number |
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| Read decimals What can you say about these three numbers? (they are equal) What can you conclude about the zeros that end a decimal? (you don’t have to write them, they don’t change the number) You can add zeros at the end of a decimal fraction or discard zeros, but this will not change the decimal fraction. The same fraction is written. |
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| A comma is placed between the whole and fractional parts. If there is no fractional digit, we replace it with 0 when writing the number. The number of digits after the decimal point must be equal to the number of zeros in the denominator of the common fraction. Write in decimal fraction: |
| Write decimal fractions from dictation. 7 point 8 2 point 25 hundredths 0 whole 92 hundredths 12 point 3 hundredths 5 point 187 thousandths 24 whole 24 thousandths 7 point 7 7 point 7 hundredths 7 point 7 thousandths 0 point 5 ten thousandths Now we are doing independent work, during which we will test our knowledge on the topic of the lesson. |
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| Independent work (5 minutes) |
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| Test yourself: Write as a decimal fraction (on a line); Check the answers in the table, putting the corresponding letter for each number (under each number without punctuation) What word did you get? WELL DONE |
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| Reflection |
| Homework: No. 647 a), 648 av), 649 a), 650 c) |
A decimal fraction differs from an ordinary fraction in that its denominator is a place value unit.
For example:
Decimal fractions are separated from ordinary fractions into a separate form, which led to their own rules for comparing, adding, subtracting, multiplying and dividing these fractions. In principle, you can work with decimal fractions using the rules of ordinary fractions. Own rules for converting decimal fractions simplify calculations, and rules for converting ordinary fractions to decimals, and vice versa, serve as a link between these types of fractions.
Writing and reading decimal fractions allows you to write them down, compare them, and perform operations on them according to rules very similar to the rules for operations with natural numbers.
The system of decimal fractions and operations on them was first outlined in the 15th century. Samarkand mathematician and astronomer Dzhemshid ibn-Masudal-Kashi in the book “The Key to the Art of Counting”.
The whole part of the decimal fraction is separated from the fractional part by a comma; in some countries (the USA) they put a period. If a decimal fraction does not have an integer part, then the number 0 is placed before the decimal point.
You can add any number of zeros to the fractional part of the decimal on the right; this does not change the value of the fraction. The fractional part of a decimal is read at the last significant digit.
For example:
0.3 - three tenths
0.75 - seventy-five hundredths
0.000005 - five millionths.
Reading the whole part of a decimal is the same as reading natural numbers.
For example:
27.5 - twenty seven...;
1.57 - one...
After the whole part of the decimal fraction the word “whole” is pronounced.
For example:
10.7 - ten point seven
0.67 - zero point sixty-seven hundredths.
Decimal places are the digits of the fractional part. The fractional part is not read by digits (unlike natural numbers), but as a whole, therefore the fractional part of a decimal fraction is determined by the last significant digit on the right. The place value system of the fractional part of the decimal is somewhat different than that of natural numbers.
- 1st digit after busy - tenths digit
- 2nd decimal place - hundredths place
- 3rd decimal place - thousandths place
- 4th decimal place - ten-thousandth place
- 5th decimal place - hundred thousandths place
- 6th decimal place - millionth place
- 7th decimal place - ten millionth place
- The 8th decimal place is the hundred millionth place
The first three digits are most often used in calculations. The large digit capacity of the fractional part of decimals is used only in specific branches of knowledge where infinitesimal quantities are calculated.
Converting a decimal to a mixed fraction consists of the following: the number before the decimal point is written as an integer part of the mixed fraction; the number after the decimal point is the numerator of its fractional part, and in the denominator of the fractional part write a unit with as many zeros as there are digits after the decimal point.
Lessonmathematics in 5th grade on the topic “Decimal notation of fractional numbers”
Subject: The concept of a decimal fraction. Reading and writing decimals.
Objective of the lesson: introduce the concept of decimal fractions, their correct reading and writing.
Tasks:
Organize the work of students to study and initially consolidate the concept of “decimal fraction” and the algorithm for writing decimal fractions.
Create conditions for the formation of UUD:
Communicative UUD: listening skills, discipline, independent thinking.
Regulatory UUD: understand the educational task of the lesson, carry out the solution of the educational task under the guidance of the teacher, determine the purpose of the educational task, control your actions in the process of its implementation, detect and correct errors, answer final questions and evaluate your achievements
Personal UUD: formation of educational motivation, the need to acquire new knowledge.
Lesson type: lesson on learning new material
Lesson construction technology: problem method, work in pairs
Forms of work: individual, frontal, conversation, work in pairs.
Organization of student activities in the classroom:
They independently identify the problem and solve it;
Independently determine the topic and goals of the lesson;
Derive a rule;
Work with the textbook text;
Answer questions;
Solve problems independently;
Evaluate themselves and each other;
They reflect.
Teaching methods: verbal, visual - illustrative, practical
Resources: multimedia projector, presentation.
Educational and methodological support: textbook"Mathematics. 5th grade” author N.Ya. Vilenkin; CD “Mathematics. Teaching according to new standards. Theory. Methodology. Practice. Publishing house "Uchitel".
| Lesson stage | Teacher activities | Student activity |
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| 1. Org. moment Determining needs and motives. 1 min | Hello guys! I would like to start the lesson with the words of the famous German poet and thinker I. Goethe: « Numbers (numbers) do not rule the world, but they show how the world is ruled." And today we will also plunge into the world of numbers and numbers. | Greeting students; checking the class's readiness for the lesson; organization of attention. | Greetings from teachers |
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| 2. Setting goals and objectives, updating knowledge | Guys, raise your hands who has ever seen recordings like: 3.5 and 1.56 Guys, where did you find these records? These entries represent fractions. The name of these fractions is encrypted. Let's formulate the topic and purpose of the lesson together. Today we are starting to study a very important, interesting and new topic for you. What interesting and new things would you like to know about decimal fractions? Today in class we will learn to write fractions in a new way. Write down the topic of the lesson “Decimal notation of fractional numbers” (slide ) . Read the fractions. What two groups can they be divided into? But the new notation can not be applied to all ordinary fractions. Who guessed which ones? | Asks questions. Offers to answer questions. | The guys solve the puzzle. Students formulate the topic of the lesson. Determine the objectives of the lesson. Write down the topic of the lesson. Read fractions. -All fractions have one and zero in the denominator. -Right and wrong |
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| 3. Learning new material | How can I write fractions differently? Look at the table ( slide ).
So, the problem was how to write ordinary fractions and mixed numbers in a new way. | Let's look at how to write a mixed number as a decimal fraction: (write in a notebook) From the examples considered, we will draw a conclusion and obtain the rule What pattern did you notice? A. 0.037 A. 3.5216 Create an algorithm for converting ordinary fractions to decimals. | the number of zeros is the same as the number of digits after the decimal point Students create an algorithm for converting fractions to decimals. |
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| 4. Physical education minute | http://videouroki.net/ | ||||||||||||||||||||||||||||||
| 5.Primary consolidation, pronunciation in external speech | In Russia, for the first time, decimal fractions were mentioned in the Russian mathematics textbook - “Arithmetic”. We can find out its author if we write fractions and mixed numbers as decimals. (Mixed numbers are written on the board, and decimals are written on cards with a letter on the back. As students complete the task, they form a word.) (M) Doing exercises according to the textbook: 1117, 1120 | Primary consolidation is carried out through commenting on each sought-after situation, speaking out loud the established algorithm of action (what I’m doing, why, what’s going on, what’s happening | Students receive the word " MAGNITSKY" |
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| 6.Independent work. Standard check. | 1. Work in a notebook(on one's own). Write down the correct fractions in your notebook (in a column). Replace them with decimals. Examination (slide ) Now write out the improper fractions and replace them with decimals. Examination (slide ) | ||||||||||||||||||||||||||||||
| 7. Evaluation of the lesson results. Summing up the lesson (reflection). | What topic did we study today? What tasks did we set today? Are our tasks completed? | Answer questions. |
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| 8. Information about homework. | Homework. Find information (articles, some other data in any periodical literature) that contains decimal fractions. Execute No. 1139.1144 (a) Study paragraph 30 | Students write down homework depending on the level of mastery of the lesson topic |
Sections: Mathematics
Subject: The concept of decimal fraction. Reading and writing decimals.
Goals:
- Formation of knowledge and skills to write and read decimal fractions. Introduce students to new numbers - decimals (a new way of writing numbers)
- Develop intuition, conjecture, erudition and mastery of mathematical methods.
- Arouse mathematical curiosity and initiative, develop a sustainable interest in mathematics.
- Foster a culture of mathematical thinking.
Developmental goal: Formation of skills of self-assessment and self-analysis of educational activities.
Problem-based - developmental lesson (combined)
Stages:
1) problematic situation;
2) problem;
3) searching for ways to solve it;
4) problem solving
Lesson motto:
Lesson Objective
Epigraphs:
“You can’t learn math by watching your neighbor do it.”
(poet Nivey)
“You have to have fun learning... To digest knowledge, you have to absorb it with appetite”
(Anatole France)
Equipment:
- individual cards - tasks;
- task cards for working in pairs;
- visibility for oral work, for historical reference;
- magnetic board
Repetition:
- Common fractions
- Geometric shapes
Lesson progress
The ancient Greek poet Niveus argued that mathematics cannot be learned by watching your neighbor do it. Therefore, today we will all work actively, well and with benefit to the mind.
I. “The Finest Hour of the Common Fraction” - oral work
First round
| 1 | |||||||
Second round “Logical chains”
Arrange in ascending order.
Third round.
The student made a mistake when applying the basic
properties of fractions. Find the mistake!
Fourth round
Learning a new topic
Let's look at the table of categories and answer the questions:
| Class of thousands |
Unit class |
||||
Questions:
- How does the position of the unit change in each subsequent line compared to the previous one?
- How does this change its significance?
- How does the value of the corresponding number change?
- What arithmetic operation corresponds to this change?
Conclusion: by moving the unit one digit to the right, each time we decreased the corresponding number by 10 times and did this until we reached the last digit - the units digit.
Is it possible to reduce one by 10 times?
Certainly,
Problem: But there is no place for this number in our tables of ranks yet.
Think about how you need to change the table of digits so that you can write the number in it.
We reason that we need to move the number 1 to the right by one place.
Likewise:
Give names to the categories : tenths, hundredths, thousandths, ten-thousandths, etc. integer part fractional part
| hundreds | thousandths |
||||
2 units 3 tenths
2 units 3 hundredths
And in order to write numbers outside the table, we need to separate the whole part from the fractional part with some sign. We agreed to do this using a comma or period. In our country, as a rule, a comma is used, and in the USA and some other countries, a period is used. We write and read the numbers as follows:
a) 2.3 or 2.3 (two point three or two, comma, three or two, point, three)
b) 2.03 or 2.03 (two point three hundredths or two, comma, zero, three or two, dot, zero, three)
Rule: If a comma (or period) is used in the decimal notation of a number, then the number is said to be written as a decimal fraction.
For brevity, the numbers are simply called in decimal fractions.
Note that the decimal fraction is not a new type of number, but a new way
recording numbers.
So, the motto of our lesson: “Have excellent knowledge on the topic “Decimal Fractions”
Lesson Objective: prove that fractions cannot put us in a difficult position.
Now let’s visit the “Historical Village”
Fractions appeared in ancient times. When dividing up spoils, when measuring quantities, and in other similar cases, people encountered the need to introduce fractions. Operations with fractions in the Middle Ages were considered the most difficult area of mathematics. To this day, the Germans say about a person who finds himself in a difficult situation that he “fell into fractions.” To make working with fractions easier, decimals were invented. They were introduced into Europe in 1585 by a Dutch mathematician and engineer. Simon Stevin. Here's how he represented the fraction:
14,382, 14 0 3 1 8 2 2 3
In France, decimal fractions were introduced Francois Viet in 1579; his fraction notation: 14.382, 14/382, 14
And we have expounded the doctrine of decimal fractions Leonty Filippovich Magnitsky in 1703 in the mathematics textbook “Arithmetic, that is, the science of numbers”
Here are some other ways to represent decimals:
14. 3. 8. 2. ;
Charger(musical accompaniment)
II. Exercises
- Record the topic of the lesson.
- The first table is to write down the numbers yourself.
- The second table is to write down the numbers by digit.
III. Recess– is carried out in order to maintain a good mood, good spirits, and a mathematical attitude.
Anatole France once said: “You have to have fun learning...To digest knowledge, you have to absorb it with appetite”
Orally:
- Vitya Verkhoglyadkin found the correct fraction, which is greater than 1, but keeps his “discovery” secret. Why?
- Vitya Verkhoglyadkin drew 11 diameters of a circle. Then he counted the number of radii drawn and got the number 21. Is his answer correct?
- A detachment of soldiers was walking: ten rows of seven soldiers in a row. How many?
a) they were mustachioed.
How many mustachioed soldiers were there?
How many mustacheless soldiers were there?
b) they were big-nosed.
How many big-nosed soldiers were there?
How many snub-nosed soldiers were there?
Write: = 0.8; = 0.4
IV. Repetition - developmental exercises (work in pairs)
Lake Rebusnoye(Application)
V. Lesson summary.
Reflection.
What new things have you learned?
- What did you find difficult?
- What have you learned?
- What problem was posed in class?
- Did we manage to solve it?
Evaluation of your work (on pieces of paper with tables of ranks). Write how you learned the lesson material.
- Got good knowledge.
- I mastered all the material.
- I partially understood the material.
VI. Homework. No. 38.1, 38.2, Workbook (page 28)