Do I include number itself when talking about divisors?

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Here is question which I answered wrong.

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n is 2 * 2 * 2 * 2 * 3 * 3 * 5 * 5 and its sqrt is 60. My thought process was that it's answer B because the smallest number divisible by 36 is 72 which fits into condition d > 60. But right answer is C.

Could you please tell me why ? Did they include 36 for (2) into the list of possible values of d too ?

Thanks!
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by nervesofsteel » Thu Apr 09, 2009 12:41 am
yes .. number 36 is considered while evaluation option 2....

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expert wrote:Here is question which I answered wrong.

Image

n is 2 * 2 * 2 * 2 * 3 * 3 * 5 * 5 and its sqrt is 60. My thought process was that it's answer B because the smallest number divisible by 36 is 72 which fits into condition d > 60. But right answer is C.

Could you please tell me why ? Did they include 36 for (2) into the list of possible values of d too ?

Thanks!
yes you need to consider the number itself

Stmt I

if d = 10

d is a divisor of n but d is not greater than n^1/2

Insuff

Stmt II

if d = 36

d is a divisor of n but d is not greather than n^1/2

Insuff

Stmt I & II

lc.m of 10 and 36 = 180

d is a divisor of n and d > n^1/2

[spoiler]Suff

C[/spoiler]
SACX