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# If r and s are each greater than 0, is (r + n)/(s + n) >

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If r and s are each greater than 0, is (r + n)/(s + n) > [#permalink]  18 Aug 2009, 22:19
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If r and s are each greater than 0, is (r + n)/(s + n) > r/s?

(1) n > 0
(2) r < s
[Reveal] Spoiler: OA

Last edited by Bunuel on 13 Dec 2012, 08:05, edited 1 time in total.
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Re: Arithmatic [#permalink]  18 Aug 2009, 22:52

Anytime we add two positive numbers to a fraction the number gets larger than the original fraction.

Statement 1 says exactly that

Statement 2 is insufficient becasue we need to know that sign of n
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Re: Arithmatic [#permalink]  19 Aug 2009, 03:25
The answer should be A, thanks for explanation
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Re: Arithmatic [#permalink]  19 Aug 2009, 05:10
Answer should be C.
must have both conditions.

e.g
r=3, s=2, n=1
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Re: Arithmatic [#permalink]  19 Aug 2009, 09:29
sher676 wrote:

Anytime we add two positive numbers to a fraction the number gets larger than the original fraction.

That's only true if your fraction has a positive numerator and denominator (which we know in this question) *and* if the overall value of the fraction is less than 1. If the value of the fraction is greater than 1, then adding the same positive value to the numerator and denominator will decrease the value of the fraction. For example, if you add 1 to the top and bottom of the fraction 2/3, the value increases to 3/4. If you add 1 to the top and bottom of the fraction 3/2, the value decreases to 4/3.
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Re: Arithmatic [#permalink]  20 Aug 2009, 00:41
Should be C.

St 1. if r and s each equal to the same number say 2 it becomes insuff.
st 2. we don't know n's sign

Together Sufficient, hence C
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Re: If r and s are each greater than 0, is (r + n)/(s + n) > [#permalink]  13 Dec 2012, 08:00
Hi Experts i think the answer should be B
but OA as per grockit is C

here is my aproach:-
working on stem
doing cross multiplication we get an equation
rs + ns > rs + nr
simplifying we get
S>R
so our question becomes Is s > r
B gives the solution directly
am i missing something...
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Re: If r and s are each greater than 0, is (r + n)/(s + n) > [#permalink]  13 Dec 2012, 08:11
Archit143 wrote:
Hi Experts i think the answer should be B
but OA as per grockit is C

here is my aproach:-
working on stem
doing cross multiplication we get an equation
rs + ns > rs + nr

simplifying we get
S>R
so our question becomes Is s > r
B gives the solution directly
am i missing something...

We cannot cross-multiply here since we don;t know the sign of s+n.

If r and s are each greater than 0, is (r + n)/(s + n) > r/s?

(1) n > 0. Since both n and s are positive, then we can safely cross-multiply and the question becomes: is rs+ns>rs+nr? --> is ns>nr? --> reduce by positive n: is s>r? We don't know that. Not sufficient.

(2) r < s. Not sufficient.

(1)+(2) the question from (1) became: s>r? The second statement answers it. Sufficient.

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Re: If r and s are each greater than 0, is (r + n)/(s + n) >   [#permalink] 13 Dec 2012, 08:11
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