Is x a multiple of y?

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Is x a multiple of y?

by CappyAA » Tue Aug 12, 2008 5:13 pm
If x and y are integers greater than 1, is x a multiple of y?

(1) 3y^2 +7y = x
(2) x^2 - x is a multiple of y




Thanks,
Cappy

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by sudhir3127 » Wed Aug 13, 2008 3:13 am
IMO A.

statement 1 can be written as

y(3y + 7) = x
means y times some integer ( 3y + 7 will be an integer because x, y are intergers) is X

hence x is a multiple of y.

statement 2 can be written as

x( x-1) = y
will be sufficient only id x is a multiple of y.
but in this case there are 3 options.
x is a multiple of y
x-1 is a multiple of y
and both X and x-1 arent the multiple of y.

hence insufficient

hope it helps...

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by CITI29 » Mon Aug 18, 2008 7:09 am
Hi sudhir , if the question was if y is multiple of x?...then wld second statement be sufficient?

pls clarify my doubt

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by coffee5251 » Thu Jan 08, 2009 5:19 am
Can someone please explain this? I plugged in numbers and am not getting A.

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by DavoodBeater » Thu Jan 08, 2009 6:42 am
to clarify the second stat.:

x^2 - x is a multiple of y
=>
x^2 - x = ky
=>
x(x-1) = ky
=>
x/y = k/(x-1) : which k/(x-1) can be integer and cannot be integer.

=> answer is A.

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by aj5105 » Fri Jan 09, 2009 9:46 am
yup A.