CH 3

Multiplying and Dividing Fractions and Decimals Study Guide A

Study Guide 3B

Divide. Write you answer in simplest form.

1. 4 ÷ 5/8

2. 1/3 ÷ 1/9

3. 3/4 ÷ 1 1/2

4. 1 1/5 ÷ 2 1/2

Multiply.

5. 0.5 x 7

6. 0.064 x 7

7. 2.5 x 0.9

8. 3.48 x 4.6

Divide.

9. 3.5 ÷ 0.5

10. 0.64 ÷ 0. 8

Solve. Show your work.

11. If 20 gallons of water are poured into 1/4 gallon containers, how many full containers can be filled?

12. Paul buys 10.5 square feet of carpet. The carpet costs $ 8.20 per square foot. How much does Paul pay for the carpet?

13. Sue has 8 sheets of colored paper. She uses 6 sheets to make posters. She cuts the remaining paper into equal rectangles to make greeting cards. Each rectangle is 1/3 of a sheet of colored paper. How many greeting cards does Sue make?

14. Joe buys 4 flats of flowers. He plants 3/5 of the flowers and then divides the remaining flowers among 4 friends. What fraction of a flat of flowers does each of Joe's friends get?

15. Cali collected some toys for a charity. She donated 2/3 of the toys to Charity A. Then she donated 1/4 of the remaining toys to Charity B. After the two donations Cali had 11 toys left. How many toys did she originally collect?

ANSWER KEY:

1. 4 ÷ 5/8 4/1 x 8/5 = 32/5 = 6 2/5

2. 1/3 ÷ 1/9 1/3 x 9/1 = 9/3= 3

3. 3/4 ÷ 1 1/2 3/4 ÷ 3/2 = 3/4 x 2/3 = 1/2

4. 1 1/5 ÷ 2 1/2 = 6/5 ÷ 5/2 = 6/5 x 2/5 = 12/25

5. 0.5 x 7 = 3.5

6. 0.064 x 7 = 0.448

7. 2.5 x 0.9 = 2.25

8. 3.48 x 4.6 = 16.008

9. 3.5 ÷ 0.5 = 7

10. 0.64 ÷ 0. 8 = 0.8

11. If 20 gallons of water are poured into 1/4 gallon containers, how many full containers can be filled?

20 ÷ 1/4 = 20 x 4 = 80 containers.

12. Paul buys 10.5 square feet of carpet. The carpet costs $ 8.20 per square foot. How much does Paul pay for the carpet?

10.5 x $ 8.20 = $86.10

13. Sue has 8 sheets of colored paper. She uses 6 sheets to make posters. She cuts the remaining paper into equal rectangles to make greeting cards. Each rectangle is 1/3 of a sheet of colored paper. How many greeting cards does Sue make?

8 - 6 = 2 2 ÷ 1/3 = 2 x 3/1 = 6

14. Joe buys 4 flats of flowers. He plants 3/5 of the flowers and then divides the remaining flowers among 4 friends. What fraction of a flat of flowers does each of Joe's friends get?

All - 3/5 = 2/5 left. 2/5 ÷ 4 = 2/5 x 1/4 = 2/20 = 1/10 of a flat each

15. Cali collected some toys for a charity. She donated 2/3 of the toys to Charity A. Then she donated 1/4 of the remaining toys to Charity B. After the two donations Cali had 11 toys left. How many toys did she originally collect?

ALL - 2/3 = 1/3 1/3 x 1/4 = 1/12 of remaining donated. All of remaining - 1/12 of remaining = 11/12 remaining. 11/12 = 11 toys 12/12 = 12 toys 12/12 is 1/3 of all toys collected. 3/3 of all toys would be 12 toys x 3 = 36 toys.