If n is an integer....

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If n is an integer....

by The Jock » Fri Jul 09, 2010 1:20 am
If n is an integer, is (50-n/n) an integer?
(1) n > 4
(2) n^2 = 25

I understand that option 1 is not sufficient because n can be any value...
Option 2 gives us two value of n, n = +5 and n=-5...
So my question is, "Is option 2 itself sufficient"?
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by papgust » Fri Jul 09, 2010 1:55 am
IMO statement II is SUFFICIENT as you repeatedly get a YES to the question "is (50-n/n) an integer?" for both +5 and -5.
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by Rahul@gurome » Fri Jul 09, 2010 8:09 pm
(1) is NOT SUFFICIENT as n can take any value.

(2) n^2 = 25 implies n = +5, -5
If n = +5, (50 - n)/n = (50 - 5)/5 = 9, which is an integer.
If n = -5, (50 - n)/n = (50 + 5)/-5 = -11, which is an integer.
So, for both values of n we get (50 - n)/n to be an integer and the answer to the main question is "Yes".

So, (2) is SUFFICIENT.

The correct answer is (B).
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