Divisors question !

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Divisors question !

by sohrabkalra » Fri Dec 02, 2011 11:58 pm
if x=3y,where y is a prime number greater than 2, how many different positive even divisors does x have, including x?

A)0
B)1
C)2
D)3
E)It can not be determined from the information given !

OA and doubt after discussion !

Updated : OA: A
Last edited by sohrabkalra on Sat Dec 03, 2011 12:26 am, edited 1 time in total.

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by LalaB » Sat Dec 03, 2011 12:19 am
A is the answ

x=3y y>2
since y cant be 2 and is a prime number ,then x and y are odd. so, even divisors are 0

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by pemdas » Sat Dec 03, 2011 12:24 am
if y is prime greater than 2 then it's odd. Hence odd multiplied by odd must be odd
x will have no even divisor
a
sohrabkalra wrote:if x=3y,where y is a prime number greater than 2, how many different positive even divisors does x have, including x?

A)0
B)1
C)2
D)3
E)It can not be determined from the information given !

OA and doubt after discussion !
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by sohrabkalra » Sat Dec 03, 2011 12:29 am
Dont you think divisor should be replaced by factors for a clear GMAT level problem, coz say in a/b, we call b divisor even though it might not be a factor of A ? or is the language ok according to GMAT standards?

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by pemdas » Sat Dec 03, 2011 12:34 am
don't confuse, if a/b is integer (here the same is implied, even divisor means at least integer condition is met, as only integers can be odd or even) then 'b' is always a factor of 'a'
sohrabkalra wrote:Dont you think divisor should be replaced by factors for a clear GMAT level problem, coz say in a/b, we call b divisor even though it might not be a factor of A ? or is the language ok according to GMAT standards?
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by Ian Stewart » Sat Dec 03, 2011 4:48 pm
sohrabkalra wrote:Dont you think divisor should be replaced by factors for a clear GMAT level problem, coz say in a/b, we call b divisor even though it might not be a factor of A ? or is the language ok according to GMAT standards?
I don't know quite what it is about the wording of this question that you find ambiguous, but the words 'divisor' and 'factor' mean the same thing in Number Theory. The integer b is a divisor (or factor) of the integer a if a/b is also an integer.
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