Is 300 a factor of Q

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Source: — Data Sufficiency |

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by gmatmachoman » Tue Jul 13, 2010 9:56 am
deepak_free wrote:Is 300 a factor of Q?

(1) 150 is a multiple of Q.

(2) 200 is a factor of Q
Pick C

st 1: Q= 300, 150 is a multiple of Q. : 300 a factor of Q --YES
Q=450 ,150 is a multiple of Q. : 300 a factor of Q --NO

Insufficient

st 2:
Q=600 , 200 is a factor of Q : 300 a factor of Q --YES
Q= 400 ,200 is a factor of Q : 300 a factor of Q -- NO

Insufficient

Combining st1 & st 2

Try taking LCM of 150,200 ---- (600)

So when Q is for all multiples of 600, then 300 a factor of Q

Try few cases :
Q=1200, Is 300 a factor of Q ?? YES
Q= 2400 Is 300 a factor of Q?? YES....

Pick C

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by deepak_free » Tue Jul 13, 2010 10:00 am
Thanks

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by Patrick_GMATFix » Tue Jul 13, 2010 10:25 am
deepak_free wrote:Is 300 a factor of Q?

(1) 150 is a multiple of Q.

(2) 200 is a factor of Q
i disagree with gmatmachoman's answer; particularly with his evaluation of statement 1. If 150 is a multiple of Q, then Q is a number such as 1, 2, 3, 5....to at most 150. Thus 300 cannot be a factor of Q. 300 is a factor of 300, 600, 900... but Q is at most 150. Thus statement 1 by itself would be sufficient because it guarantees an answer of NO. 300 is not a factor of Q.

Furthermore, deepak where is this question from? The statements contradict each other, which means that this cannot be a valid GMAT question.
(1) 150 is a multiple of Q. Means Q is part of the set {1, 2, 3, 5, 6....150}. Q cannot be greater than 150 (how can a number be greater than its multiple?).
(2) 200 is a factor of Q. Means Q is part of the set {200, 400, 600, 800....} Q cannot be less than 200 (how can a number be less than its factor?)

There is no single value of Q that agrees with both statements, so this is an invalid question

Note: The GMAT generally deals only with positive factors and multiples unless stated otherwise, so keep that in mind.

Please state the source of the question,
-Patrick
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by gmatmachoman » Tue Jul 13, 2010 10:32 am
Patrick,

Nice catch....!!

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by Patrick_GMATFix » Tue Jul 13, 2010 11:17 am
gmatmachoman wrote:Patrick,

Nice catch....!!
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