### Multiplying fractions Homework

Wednesday, April 29, 2009
One week, Kristi works 3 days for 3 1/2 hours each day. She makes \$9 an hour.

A) How many hours did Kristi work in 1 week?

Hours in week = Days x Hours per day

HW = 3 x 3 1/2

3 x 3 1/2 =

3 x 3 = 9

3 x 1/2 = 1 1/2

Kristi worked 10 1/2 hours.

B) How much did she earn in one week?

Weekly\$ = (wage x H) x 3

9 x 3 1/2

9 x 3 = 27

9 x 1/2 = 4 1/2

\$31.50 x 3 = \$92.50

In 1 week Kristi earned \$92.50.

In one Earth day Jupiter completes 2 2/5 rotations. How many does it complete in one week?

1 day = 2 2/5 rotations

1 week = 1 day x 7

7 x 2 2/5 =

7 x 2 = 14

7 x 2/5 = 14/5

14/5 = 2 4/5

In one week, Jupiter completes 16 4/5 rotations.

A boat is sailing 8 1/2 km/h. If no conditions change, how far will it sail in 1 1/3h?

8 1/2 x 1 1/3=

17/2 x 4/3 = 68/6
= 11 2/6

It will sail 11 2/6 km.

The distance to Grandma's house is 4/5 the distance to Uncle Glen's house. If Uncle Glen is 3 1/2 hours away, how long will it take to get to Grandma's house?

3 1/2 x 4/5 =

7/2 x 4/5 = 28/10
= 14/5
= 2 4/5

It would take 2 and 4/5 or 2 hours and 45 minutes.

It takes 3/5 of a tank of gas to get to work and back each day. How many tanks would it take
to go to work and back for 5 days?

3/5 x 5 =

3/5 x 5/1 = 15/5
= 3

It would take 3 full tanks of gas.

Owen is 2 1/4 times older than Robin. When Robin turns 8, how old will Owen be?

2 1/4 x 8 =

9/4 x 8 = 72/4
= 18

Owen will be 18.

A karate club is testing candidates. If it takes 3 1/4 hours to test 4 candidates, how long will it take to test 3 groups of 4 candidates each?

3 1/4 x 3 =

13/4 x 3/1 = 39/4
= 9 3/4

It will take 9 3/4 hors or 9 hours and 45 minutes to test 12 candidates.