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Janet can shovel snow from her driveway in 55 minutes. Bill can do the same job in 45 minutes. How long would it take Janet and bill to shovel the driveway if they worked together?

User Allen Chou
by
6.0k points

1 Answer

3 votes

Answer:

It would take 24.75 minutes for them to shove the driveway if they worked together.

Explanation:

The together rate is the sum of each separate rate.

In this problem:

Together rate: 1/x

Janet's rate: 1/55

Bill's rate: 1/45.

So

Together rate = Janet's rate + Bill's rate

We have to find x


(1)/(x) = (1)/(55)+(1)/(45)

The least common multiple between 55 and 45 is 495. So


(1)/(x) = ((495)/(55) + (495)/(45))/(495)


(1)/(x) = (9 + 11)/(495)


(1)/(x) = (20)/(495)


20x = 495


x = (495)/(20)


x = 24.75

It would take 24.75 minutes for them to shove the driveway if they worked together.

User Scott Thompson
by
5.3k points
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