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CAT Exam 4 - Jim and Tom Jacket

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kadeneclarke
 Post subject: CAT Exam 4 - Jim and Tom Jacket
 Post Posted: Sun Jun 26, 2011 10:37 pm 
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Students


Posts: 6
I do not understand why my approach to the following CAT question is incorrect:-

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

SOLN

Jacket Price = 4x = 5y

(1) x=0.8y =>4*0.8y = 5y. I then solved for y to determine 5y

(2) x = 43.75-y => 4(43.75-y) = 5y. Again I solved for y to determine the price of the jacket, 5y.

As such, I chose (d) for my answer. MGMAT's soln treated this as a rate question - not sure why- and the result was different from what I got. Can someone say why is my approach incorrect?
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kadeneclarke
 Post subject: Re: CAT Exam 4 - Jim and Tom Jacket
 Post Posted: Tue Jun 28, 2011 4:38 am 
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Students


Posts: 6
Sorry, made a bobo on this one. 5y=4x=Price of Jacket but based on (1) 5*0.8x is the same as 4x so (1) alone is not sufficient. Just the kinda mistake I don't need..aaah!
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jnelson0612
 Post subject: Re: CAT Exam 4 - Jim and Tom Jacket
 Post Posted: Sat Jul 02, 2011 10:40 pm 
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ManhattanGMAT Staff


Posts: 1857
Glad you figured it out!

_________________
Jamie Nelson
ManhattanGMAT Instructor
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