SOLUTION: Two men dig a trench 30 m long in 3 days. How long would it take 3 men to dig a trench 15 m long working at the same rate?

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Question 1004209: Two men dig a trench 30 m long in 3 days. How long would it take 3 men to dig a trench 15 m long working at the same rate?
Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
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Two men dig a trench 30 m long in 3 days. How long would it take 3 men to dig a trench 15 m long working at the same rate?
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30%2F%282%2A3%29 = 15%2F%283%2Ax%29.

This proportion equalize the rate of work in these two cases.

x is unknown number of days for 3 men to dig a trench 15 m long.

Solve the proportion for x.

The answer is: one day.

You may get the same answer by noticing that the rate of 1 man is 5 m of the trench per day.
It follows the first part of the condition.

The way of equalizing the rates is the universal and most direct method to solve problems like this one.