P and Q. G =?

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P and Q. G =?

by sanju09 » Fri May 21, 2010 4:08 am
G, P, and Q are integers, P = K + 6; G is the greatest common factor of P and Q. G =?

(1) Q = 2531.

(2) Q = K + 7.
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by liferocks » Fri May 21, 2010 4:14 am
From 1,
no information about P...not sufficient

From 2
P and Q are consecutive integers and consecutive integers are all always co-prime..hence G=1...sufficient

Ans option B
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by gmatmachoman » Fri May 21, 2010 11:04 am
liferocks wrote:From 1,
no information about P...not sufficient

From 2
P and Q are consecutive integers and consecutive integers are all always co-prime..hence G=1...sufficient

Ans option B
LR, what will be the HCF of (0,1) ???

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by kel2010 » Fri May 21, 2010 12:40 pm
LR, what will be the HCF of (0,1) ???
gcd= 1

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by liferocks » Fri May 21, 2010 5:52 pm
gmatmachoman wrote:
liferocks wrote:From 1,
no information about P...not sufficient

From 2
P and Q are consecutive integers and consecutive integers are all always co-prime..hence G=1...sufficient

Ans option B
LR, what will be the HCF of (0,1) ???
GCD of (a,0)=|a| for a not equal to zero since any number is a divisor of 0, and the greatest divisor of a is |a|.
So, HCF of (0,1)=1
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by gmatmachoman » Fri May 21, 2010 9:13 pm
Then B is the best answer!

as LR rightly pointed out, consecutive integers are co-prime...HCF is 1