Try this:

S2. If r=2.1 and y=0.1, then

rs=0.21 and r+s=2.2

So, rs/(r+s)=0.21/2.2 < 1/2

What if r=4 and y=8, then

rs=32 and r+s=12

So, rs/(r+s)=32/12 > 1/2

So, Insuff.

Well, I just figured out that for r>1 and s>1 this expression holds true.

nverma wrote:

ykaiim wrote:

Is rs/(r+s)>1/2 ?

1. r>1 and s>1

2. r>2 and s>0

Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient

Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient

BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient

EACH statement ALONE is sufficient

Statements (1) and (2) TOGETHER are NOT sufficient

IMHO D

Statement 2:

Is rs/(r+s)>1/2 >>>> Is rs/(r+s)-1/2 >0 >>>> Is (2*r*s-(r+s))/(r+s) >0

Now given r and s both are positive...so r+s is positive >>> so denominator is positive..

lets have a look at numerator

so the question becomes Is (2*r*s-(r+s)) >0

Is 2rs + (r-s) > 0

Now |2rs| will be greater than |s-r|, So 2rs + (r-s) > 0. Sufficient

Statement 1:

Same way as mentioned above, this statement is sufficient.

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