positive difference

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by snakedoc » Fri Aug 26, 2011 2:25 am
The Answer is C itself.

In First case it is .25hr and in second case it is .5hr so the difference is .25hr


Please correct me if I am wrong.

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by gmatboost » Fri Aug 26, 2011 8:15 am
C is correct, unless we have all misinterpreted the question.

In the first case,
2 + 4x = 12x
2 = 8x
x = 0.25

In the second case,
(3/2)(2 + 4x) = 12x
3 + 6x = 12x
3 = 6x
x = 0.5
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