(2) 1÷32÷0.05÷0.25÷0.5;

(3)4.83×0.59+0.4 1× 1.59-0.324×5.9

(4) There is a four-digit number. Add a decimal point after one digit and add it to four digits, and the number is 4003.64. Find this four-digit number

(5) The difference between a large number and a decimal number is 49.23. If the decimal point of a small number is shifted to the right by one place, it is equal to a large number. Find these two numbers.

(6) The sum of sizes is 3 1.24. If the decimal point of a big number is shifted one place to the left, it is equal to a small number. Find these two numbers.

(7) When circulating decimal numbers and decimal places, the digits are all 6 for the first time?

Decimal divided by integer

Doctor's tip: Remember to align the decimal point of quotient with the decimal point of dividend.

Textbook link:

1, oral calculation.

23.6÷ 10= 10÷4= 3÷6= 0.36÷3=

8.4÷2= 0.05×40= 40÷50= 5.7+ 13= 6.6÷33 =

2. Fill in the blanks.

(1) Which of the following questions has a quotient less than 1 is ().

3.6÷2 ( ) 15.87÷20( ) 7.98÷8( ) 4.95÷ 1 1( )

(2)( )× 15=7.5 ( )×8=90 40.5÷( )= 15

(3)60 hours = () 84 minutes = ()

3. Is the following calculation correct? If not, what's the problem? And please correct it.

27÷ 18= 15( ) 1.56÷26=0.6( )

15

18 27 0.6

18 26 1.56

40 amendment: 1.56 amendment:

40 0

4. Calculate the following questions.

(1) 6 ÷ 24 (2) 52.95 ÷ 75 (3) 84.01÷ 31(check by multiplication)

Intelligent upgrade: 1. Write the numbers of the following questions directly according to 25×5= 125.

2.5×5=( ) 125÷5=( ) 12.5÷25=( )

1.25÷5=( ) 0. 125÷5=( ) 1250÷5=( )

2. What is the highest ranking of the following vendors? Then calculate in the form of columns.

4.95÷ 1 1 3.0 1÷7 280.8÷24 0.646÷ 19

3. Calculate the following questions continuously.

(1) Five times a number is 1 1.5. What's this number?

(2) The product of two numbers is 15.36, where one factor is 12, and what is the other number?

4. Two road construction teams, team A completed 6.48km in 8 days and team B completed 9 days10.35km.. Say which team is more efficient first, and then calculate whether you are right or not.

Intelligence:

A six-story tower has three times as many lights on each floor as on the previous one. It is known that there are two lights on the top floor. How many lights have been lit in this tower?

Fill in the blanks.

1, the divisor is fractional division. First, move the decimal point to make it a number, move the decimal point of the divisor to the right by several digits, and move the decimal point of the divisor by several digits (if there are not enough digits, end with ","), and then calculate according to the fractional division of the divisor.

2. Fill in the appropriate numbers in the brackets below.

0.36÷ 1.2=( )÷ 12=( ) 87÷0.03=( )÷3=( )

375÷0.25=( )÷25=( ) 2.4÷0.06=240( )=( )

Second, oral calculation.

0.24÷0.4 7.5÷2.5 4.8÷0. 12 2÷0.4

1.5÷3 0.03× 10 0.55÷0. 1 1 0. 1+0.02

Can you fill in the figures in other columns according to the figures in the first column?

Dividend 276 27600 27.6 0.276

Divider121.20.120.05438+02

Quotient 23 23 23

Fourth, calculate the following questions

0.396÷ 1.2= 0.756÷0.36= 27.5÷0.025=

Intelligent upgrade:

First, interesting calculations. What does the calculation result remind you of?

2 1.35÷3.5= 23.97÷4.7=

19. 19÷ 1.9= 0.20 14÷0.053=

Second, find the unknown X.

8.5–x = 0.05 0.75×x = 10.5 x÷0.23 = 0.56

Third, the application problem.

1. Xiaohong bought a pen with a unit price of 4.5 yuan, paid 20 yuan and found 6.5 yuan. How many pens did she buy?

2. Starlight community to carry out water conservation activities. Grandma Wang saved 2 1.6 yuan in the first half of the year, and Grandma Zhang saved 16.2 yuan in the first quarter. Who saves more water every month on average?

Intelligence:

Xiao Ming accidentally divided a number by 4.75 and multiplied it by 4.75 in the math exam, and the result was 406.438+025. What should be the correct answer to this question?

repeating decimal

Little doctor's tip: Do you know interesting cyclic decimals?

Textbook contact

1, fill in the blanks.

(1) A decimal, starting from a certain position in the decimal part, or appearing successively, is called a decimal.

(2) In 3.82, 5.6, 0.35, 0.002, 2.75, 3.2727 ... are finite decimal numbers, but () are cyclic decimal numbers ().

(3) 8.375375 ... can write.

2. Write the approximate values of the following cyclic decimals (keep three decimal places).

0.3333……≈ 13.67373……≈

8.534534……≈ 4.888……≈

3. Judgment (put "√" in the brackets for the right and "×" for the wrong)

(1) 1.4545 ... one decimal place is reserved) ≈ 1.4 ()

(2) The cycle segment of 2.453453 … is 435. ( )

(3) Circular decimals are infinite decimals. ( )

(4) The last digit of the decimal part of1.2323 … is 3. ( )

4. Calculate the following problems and express the quotient with cyclic decimals.

13÷ 1 1= 57÷32= 1 1.625÷9.3= 30. 1÷33=

Intelligent upgrade:

1. Can you compare the sizes of these decimals? Give it a try! (I can't get the circulation point when I send it. )

0.66○0.6 8.25○8.25 5.4 1○5.4 1

3.888○3.08 7.28○7.28 0.99○0.9999

2. Use simple symbols to represent the following cyclic decimals.

3.2525…… 17.065 165 1…… 1.066…… 0.333……

3. multiple choice questions. (Fill in the serial number of the correct answer in brackets)

The loop segment of (1) 2.235235 ... is ().

①2.235 ②2.35 ③235 ④235

(2) Among the following figures, the largest is ()

①3.8 1 ②3.8 1 ③3.8 1 ④3.8

(3) Numbers require three decimal places, and should be calculated to () decimal places.

① Two, two, three, four, four, five.

4. Application questions

Students from three classes in Grade Five took part in tree planting activities, and planted 220 trees. Class one planted twice as many trees as Class two, and Class two planted 20 more trees than Class three. How many trees are planted in each class?

Intelligence:

The sum of the two numbers is 1 1.63. Due to carelessness, Xiao Qiang moved the decimal point of an addend to the left in the calculation, and the result was 5.87. What are the first two addends?

Unit 2 Test Questions

First, knowledge and energy networks.

1, 15.68 magnification () times is 1568, and reduction () times is 0.0065.

2. The decimal part with infinite digits is called ().

3, 0.746746 ... Write () in a simple and convenient way, and write () with three decimal places.

4.0.25 hours (), 3.75 kilometers = () meters, 560 kilograms = () tons.

5. In descending order 6.16,6.16,6.16,6.166.

()& lt()& lt()& lt( )

6. Li Shifu manufactured 25 parts in 0. 15 hours, with an average of () parts per hour.

7. Please tick "√" in the brackets of the following correct questions and "×" in the brackets of the wrong questions.

(1) Cyclic decimal is infinite decimal. ( )

(2) The quotient of 2.8 ÷ 0.9 is 3, and the remainder is 1. ( )

(3) 1.998 is accurate to about 2 percentage points. ( )

(4) Infinite decimal must be greater than finite decimal. ( )

8. Choose the correct answer and fill in the brackets.

The maximum formula of (1) quotient is ()

①54÷0.36 ②5.4÷36 ③5.4÷0.36

(2) Decimals greater than 0.7 and less than 0.8 have () digits.

1 9 2 0 3 countless 4 1

(3) 3.2727 ... is () decimal.

① Finite ② Cycling ③ Not Cycling

(4) The highest order of the quotient of 2.76 ÷ 0.23 is ()

① Unit ② Ten digits ③ Hundred digits ④ Ten digits.

9. Use vertical calculation.

2.5÷0.7= (three decimal places are reserved for the obtained number) 10. 1÷3.3= (decimal representation of business cycle)

10.75÷ 12.5= (check by multiplication) 3.25×9.04= (check by division)

10, parting calculation.

6.8×0.75÷0.5 13.75÷0. 125–2.75 1.53+23.4÷7.2

Second, the application is online.

1 1, the distance from A, B and C to the urban area is 263.2 kilometers, and it takes 2.8 hours for buses to complete the journey and 3.5 hours for trucks to complete the journey. How much faster is a bus than a truck?

12, Xiaoming buys 3kg pears and 3kg apples * * and pays 20. 1 yuan, and Xiao Fang buys 1kg pears and 3kg apples * * and pays1yuan. How much are apples and pears per kilogram?

Third, the practice platform.

Teacher Luo wants to spend 1000 yuan to buy sporting goods for the school. He spent 227.5 yuan to buy five soccer balls first, and is going to use the remaining money to buy several blue balls at 30.9 yuan each. How many more blue balls can Teacher Luo buy? What other math questions do you ask?

Fourth, intellectual surfing.

Add appropriate operation symbols and brackets to the following five formulas to make the left and right sides of the straight line equal.

0.5 0.5 0.5 05 0.5=0

0.5 0.5 0.5 05 0.5=0.5

0.5 0.5 0.5 05 0.5= 1

0.5 0.5 0.5 05 0.5= 1.5

0.5 0.5 0.5 05 0.5=2