Question

You are doing yardwork with a friend. You can finish mowing the lawn in 57 minutes, while your friend can do the same amount of work in 54 minutes. How long will it take to complete the job if you work together? Round your answer to the nearest whole number.

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Answer 1

28 minutes

Explanation:

Speed = distance / time

Your speed is 1 lawn / 57 minutes. Your friend's speed is 1 lawn / 54 minutes. Working together, your combined speed is:

1/57 + 1/54

So the time it takes working together is:

Speed = distance / time

1/57 + 1/54 = 1 / t

t = 27.7 minutes

Rounded to the nearest whole number, it takes 28 minutes.