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Ratio and Proportion: Jobs

Date: 7/7/96 at 15:30:9
From: Anonymous
Subject: Ratio and Proportion: Jobs

I'm always stuck on R&P problems!

30 men can complete a job in 12 days if the number of working hours 
per day is 8. If the job is to be completed in 10 days with 24 men, 
what will be the working hours per day?


Date: 7/7/96 at 18:41:21
From: Doctor Anthony
Subject: Re: Ratio and Proportion: Jobs

The man hours to do the job are 30*12*8 = 2880 man hours.
In the second situation we let x be the number of hours per day, and 

            24*10*x = 2880
                  x = 2880/240 = 12

So the job could be done in 10 days by 24 men working 12 hours a day.

-Doctor Anthony,  The Math Forum
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Associated Topics:
Middle School Ratio and Proportion
Middle School Word Problems

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