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Data Sufficiency Problem..

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Data Sufficiency Problem..

by odod » Thu Jan 15, 2009 7:30 am
Hi folks.

Me again.


If a and B are positive intergers, what is the value of A + B?

1) A/B = 5/8
2) The greatest Common divisor of A and B is 1.

??I kno wthe answer, just my way of solving it was very long and too time consuming. Looking to see if there's an easier method.

Thanks
ODOD
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by yalanand » Thu Jan 15, 2009 7:37 am
I would bet on C..

1) A/B = 5/8

A and B can be any of the following sets ...(5,8) (10,16) etc

2) The greatest Common divisor of A and B is 1. Insuff


combining both of them we can infer

A= 5
B= 8

hence A+B = 13
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by Ian Stewart » Thu Jan 15, 2009 8:56 am
Yes, the two statements are clearly insufficient alone. If the GCD of A and B is 1, that's just another way of saying that the fraction A/B is completely reduced. So if A/B = 5/8, then A must be 5 and B must be 8.
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