4.5×3 1.5×0.4 0.05× 1.6
2.5÷5 16÷4 4.8÷8
0. 15×4 4.9÷7 8. 1÷9
First, review the old knowledge.
1. Write two division formulas according to the formula.
1.75× 18=3 1.5
( ) ( )
2. Column vertical calculation.
25.2÷6 34.5÷ 15 13.08÷24
According to the above three questions, you find that the decimal point of quotient should be aligned with the decimal point of ().
Second, the exploration of group cooperation
1, column vertical calculation
43.5÷29 18.9÷27 1.35÷ 15
2. Calculate the following questions and check them by multiplication.
15.6÷ 12 32.8÷ 16 1.35÷27
Third, classroom exercises.
1, column vertical calculation
28.6÷ 1 1 20.4÷24 3.64÷52
2. Column calculation.
(1) Divide 38.7 into three parts on average. How much is each part?
(2) It is known that the product of two factors is 36. 18, and one factor is 18. What is another factor?
3. Which quotient of the following questions is less than 1? Draw √ in ().
5. 12÷6 ( ) 80.4÷35 ( ) 0. 12÷ 12( )
4.2÷3 ( ) 9 1÷ 14 ( ) 28.6÷ 1 1 ( )
Iv. Evaluation feedback 1
1, column vertical calculation
36.9÷ 18 172.8÷24 1.25÷25
2. Application questions
(1), ***4 new fairy tales, the price is 26.8 yuan, what is the average price of each book?
(2) A rice mill grinds 1.26 tons in 8 hours. How many tons of rice does this rice mill grind on average per hour?
Verb (abbreviation of verb) evaluation feedback II
1, column vertical calculation
8. 1÷54 46.2÷ 15 15.6÷ 16
2. Practical application
(1) Among amphibians, the African frog is the champion of long jump. An African frog once set a record of jumping 7.74 meters three times in a row. How far does this African frog jump on average?
Dad took Xiao Yong to climb the mountain at the weekend. It is 7.2 kilometers from the foot of the mountain to the top of the mountain. It took them three hours to go up the mountain and two hours to go down. What is the speed of going up and down the mountain?
Can you ask other math questions?
(3) A butterfly flies 6.08km in 0.8h, and a bee flies18.2km per hour. How many times do bees fly per hour than butterflies fly per hour? (Figures shall be kept to two decimal places)