Factors of a number

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by umaa » Wed Aug 05, 2009 8:17 am
A is the right answer.

Factors can't be negative.

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by quant-master » Wed Aug 05, 2009 9:16 am
umaa wrote:A is the right answer.

Factors can't be negative.
thats correct
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by goelmohit2002 » Wed Aug 05, 2009 9:20 am
quant-master wrote:
umaa wrote:A is the right answer.

Factors can't be negative.
thats correct
Thanks All.

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by goelmohit2002 » Wed Aug 05, 2009 10:05 am
Just one query...

why not negative....

as far as I know ...factor of any integer N is any a number that gives the remainder = 0...

isn't 4 when divided by -4 gives remainder = 0 ?...or there is some condition that factors means only +ve atleast for GMAT ?

Please tell what I am missing here ?

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by Ian Stewart » Thu Aug 06, 2009 7:58 pm
Factors can certainly be negative, but you won't need to worry about this on the GMAT - every GMAT question about divisibility will be restricted to positive integers. You'll notice that GMAT questions ask for "the number of positive divisors of x", not "the number of divisors' of x", for example.
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by goelmohit2002 » Thu Aug 06, 2009 9:07 pm
Ian Stewart wrote:Factors can certainly be negative, but you won't need to worry about this on the GMAT - every GMAT question about divisibility will be restricted to positive integers. You'll notice that GMAT questions ask for "the number of positive divisors of x", not "the number of divisors' of x", for example.
Thanks a lot Ian. Actually I am really puzzled in one of the questions regarding this.....can you please look at the following link:

https://www.beatthegmat.com/hard-to-unde ... 41036.html

If we go by definition that factors can be positive and negative then answer should be E.....but I am not sure how Manhattan people are coming to answer as D ? The above is a Manhattan Question....

Does it mean that whenever factor is mentioned in a GMAT question, then it means that we have to think about only positive factors and not negative factors ?