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If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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24 Aug 2016, 04:10
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64% (02:14) correct 36% (02:02) wrong based on 102 sessions
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If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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24 Aug 2016, 05:00
This is how I tried.
Given \(\sqrt{ABC}=504\).
We write the factor of 504  2*2*2*7*3*3
Stat 1: C = 168 then A and B can be 3 or 1. (168*3*1 = 504)...we can't take unique value for A and B.
Stat 2: A is perfect square from the set 2*2*2*7*3*3 , we can take 4 and 9 and also 1..no unique value for A.
Stat 1 + Stat 2: if A is 1 and B = 3 then C = 168. Anyhow 1 is perfect square.
Option C is correct answer..



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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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25 Apr 2017, 10:43
I doubt the correct answer is C. The question is "IS B DIVISIBLE BY 2?" We are not looking for the value of B. Statment 1 is sufficient since B can only be 1 or 3. Whatever the value (1 or 3) B is not divisible by 2. Statment 2 is insufficient. Can experts advise please?
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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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04 May 2017, 00:37
msk0657 wrote: This is how I tried.
Given \(\sqrt{ABC}=504\).
We write the factor of 504  2*2*2*7*3*3
Stat 1: C = 168 then A and B can be 3 or 1. (168*3*1 = 504)...we can't take unique value for A and B.
Stat 2: A is perfect square from the set 2*2*2*7*3*3 , we can take 4 and 9 and also 1..no unique value for A.
Stat 1 + Stat 2: if A is 1 and B = 3 then C = 168. Anyhow 1 is perfect square.
Option C is correct answer.. Even though B cant have a unique value still both the possible values are not divisible by 2 IMO A should be the answer



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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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04 May 2017, 08:28
I also think answer should be A. value of B can be 1 or 3 which gives answer as No.



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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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04 May 2017, 09:06
stonecold wrote: If A, B, C are integers and \(\sqrt{ABC}=504\) . Is B divisible by 2? (1) C = 168 (2) A is a perfect square Now solve this one=> http://gmatclub.com/forum/isbdivisibl ... l#p1726368Hi stonecold good Q as so many are making errors.. The value of B can be only 1or 3 is WRONG.. Let's see the Q.. \(\sqrt{ABC}=504\) MEANS A*B*C=504*504... So if C =168, A*B=\(\frac{504*504}{168}\)=1512.. So A and B can take various combinations of values.. So statement I is insufficient... Statement II doesn't give any info alone so again insufficient.. Combined.. A*B=1512=\(3^3*7*2^3\)... So if A is perfect square, A can have either 2^2 or no 2 in it.. Thus B has to have ATLEAST one 2.. Thus answer is YES.. Sufficient C
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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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04 May 2017, 09:13
I don't think A is the answer. The first statement says, C = 168:
How can you infer (A =1 and B = 3) or (A = 3 and B = 1). If you do that, you'll get
sq rt (3 * 168 * 1) = 504 sq rt (504) = 504
I got the answer as C by guessing between C & E since A, or D can't be the answers. Following is how:
Statement 1: C = 168 So, sq rt (A * B * 168) = 504 Hence, A*B*168 = 504^2 => A*B = (504^2)/168 Doesn't give is much about B.
Statement 2: A is a perfect sq. Doesn't give is anything either.
So, A, B and D can't be the answered.
I guessed between C and E.
Please help me understand how the correct answer is C though.



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Re: If A, B, C are integers and (ABC)^(1/2) = 504 [#permalink]
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04 May 2017, 09:17
chetan2u wrote: stonecold wrote: If A, B, C are integers and \(\sqrt{ABC}=504\) . Is B divisible by 2? (1) C = 168 (2) A is a perfect square Now solve this one=> http://gmatclub.com/forum/isbdivisibl ... l#p1726368Hi stonecold good Q as so many are making errors.. The value of B can be only 1or 3 is WRONG.. Let's see the Q.. \(\sqrt{ABC}=504\) MEANS A*B*C=504*504... So if C =168, A*B=\(\frac{504*504}{168}\)=1512.. So A and B can take various combinations of values.. So statement I is insufficient... Statement II doesn't give any info alone so again insufficient.. Combined.. A*B=1512=\(3^3*7*2^3\)... So if A is perfect square, A can have either 2^2 or no 2 in it.. Thus B has to have ATLEAST one 2.. Thus answer is YES.. Sufficient C Is there a faster approach other than calculating A*B=\(\frac{504*504}{168}\)=1512? Wouldn't be able to do this question in 2 mins...




Re: If A, B, C are integers and (ABC)^(1/2) = 504
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