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shubha2110
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Jim earns x dollars per hour

by shubha2110 Wed Dec 28, 2011 7:04 am

If Jim earns x dollars per hour, it will take him 4 hours to earn exactly enough money to purchase a particular jacket. If Tom earns y dollars per hour, it will take him exactly 5 hours to earn enough money to purchase the same jacket. How much does the jacket cost?

(1) Tom makes 20% less per hour than Jim does.

(2) x + y = $43.75

In this question, the solution suggests that the 2nd statement can be used to solve by calculating the combined pay rate as
Combined rate = 1/4+1/5 = 5/20 + 4/20 = 9/20 jackets per hour Amount earned = (x+y)*9/20 = 43.75$ => Amount earned = 19.6875$. But this is not the price of the jacket, is it??

Also, here is how i calculated it:
the question says that they earn exactly the amount reqd for the jacket. So, 4x = 5y. Given relation between x and y, by substitution, x = 24.3$ so 4x = 97.2$.

Is this not correct? Why?

Thanks
Subhashini
tim
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Re: Jim earns x dollars per hour

by tim Tue Jan 10, 2012 8:23 pm

your numerical results are not correct because they are rounded, but you definitely are doing the right thing here..
Tim Sanders
Manhattan GMAT Instructor

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