Answer should be C
Question states that product of first 8 positive integers i.e. 1*2*3*4*5*6*7*8 is a multiple of a^n. What is a = ?
1. a^n = 64 ==> 2^6 or 4^3 or 8^2. So, a can be equal to 2,4 or 8. So, insufficient.
2. n=6. This alone is insufficient to answer the question.
Together, the only possiblity of n=6 is when a=2. Also, 2^6 is a factor of the product of the first 8 positive integers.
Hope this helps.
question from gmat prep
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Source: Beat The GMAT — Data Sufficiency |
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iamcste
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rossmj wrote:If the integers a & n are >1 and the product of the first 8 positive integers is a multiple of a^n, what is the value of a?
1) a^n=64
2) n=6
Qtn decomposes to
2^7*3^2*5*7 is a mutiple of a^n. a=?
1. First statment similar evalauation done above
2. n=6
if you consider a =3, 2^7*3^2*5*7 cannot be multiple of 3^6
( How can something containing 3^2 be a multiple of 3^6 given the conditions in this problem)
similarly, if yon consider any damn value for "a" other than 2, 2^7*3^2*5*7 will not be mutiple of a^6
Hint: Look at 2^7 as highest power in the multiple and a^6
so it is clear that "a" has to be 2 to meet the condition 2^7*3^2*5*7 is a mutiple of a^n
Sufficient
IMO B
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cubicle_bound_misfit
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gmatkiller2009
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can someone please explain this problem again, i still dont understand how statement 2 is the correct answer. Please do explain. Thanks
