Inequality

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Inequality

by gxj007 » Sun Sep 13, 2009 4:41 pm
Can anyone explain the best way to approach this problem? I figured it out by testing numbers but I'm sure there is a more efficient way if you understand the concept. thanks!


If m>0 and n>0, is (m+x)/(n+x) > m/n

1) m<n
2) x>0

Answer:



C) both statements combined

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by prindaroy » Sun Sep 13, 2009 8:18 pm
Picking numbers would actually be the most efficient strategy in my opinion. You could however reason this out but you have to be wary of this method. First, see that when you add the same thing to both the denominator and the numerator than the fraction will increase in value if the numerator is smaller than the denominator and the number you add is positive. Now if these conditions are not met, then the reverse will happen.

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by aim.gmat » Mon Sep 14, 2009 5:17 am
there is a rule,
given a,b > 0 and if another num x>0 is added
if a>b then a+x/b+x<a/b
if a<b then a+x/b+x> a/b
if a=b then a+x/b+x=a/b