Can You solve this "remainder" question?

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What is the remainder when integer n is dvided by 10?

(1) when n is divided by 110, the remainder is 75.
(2) When n is divided by 100, the remainder is 25.

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by cramya » Thu Jun 25, 2009 9:52 pm
D

Stmt I

n = 110q+75

110 always divisble by 10 so the remiander will be what 75 will leave when divided by 10 i.e 5

SUFF

Stmt II

n = 100q+25

100 always divisble by 10 so the remiander will be what 25 will leave when divided by 10 i.e 5

SUFF


Only prob is the 2 statements here contradict each other i.e. if we take n=75 then it does not leave a remainder 25 when divided by 100. In gmat q's this will not be the case

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by nitya34 » Fri Jun 26, 2009 1:02 am
..........
Last edited by nitya34 on Fri Jun 26, 2009 1:06 am, edited 1 time in total.

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by nitya34 » Fri Jun 26, 2009 1:04 am
agreed D

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by rahulg83 » Fri Jun 26, 2009 2:06 am
matter of seconds..:)

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by Ian Stewart » Fri Jun 26, 2009 3:03 am
cramya wrote: Only prob is the 2 statements here contradict each other i.e. if we take n=75 then it does not leave a remainder 25 when divided by 100. In gmat q's this will not be the case
Yes, n can't be 75, but the statements aren't contradictory - n could be 625, 1725, 2825, etc.
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by cubicle_bound_misfit » Fri Jun 26, 2009 5:51 am
Basically,

the question is asking ...what is the unit digit of n

Using both statements independently,
each time unit digit is 5 (use VIC method)

hence D.
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by cramya » Fri Jun 26, 2009 4:16 pm
Yes, n can't be 75, but the statements aren't contradictory - n could be 625, 1725, 2825, etc.
Thanks Ian!


Regards,
CR