score780 wrote:

Isn't it always the case that if X+Y>0 then X>-Y.

Yes IT IS TRUE ALWAYS!

X+Y > 0 take Y to the other side or subtract both the sides by Y we get:

X+Y - Y > 0 - Y

=> X > -Y

score780 wrote:

DS question:

Is X+Y positive?

1-X-Y is positive

2-Y>0

Question is is X + Y > 0

STAT1

X-Y > 0

=> X > Y

Only thing which this option tells us is that X is greater than Y

Now, X and Y can both be negative then X + Y < 0

X can be positive and Y can be negative and |Y| > |X| then X + Y <0

X can be positive and Y can be negative and |Y| = |X| then X + Y =0

X can be positive and Y can be negative and |Y| < |X| then X + Y >0

X and Y can both be positive, in this case X + Y > 0

So, NOT Sufficient

STAT2

Y > 0

This is not sufficient as we have no information about X

STAT1 and STAT2 together give us that X > Y and Y is positive so, obviously X will also be positive

Hence, X + Y >0 (because both X and Y are positive)

So, answer will be C

Hope it helps!

_________________

Ankit

You must Believe

GMAT Quant Tutor

How to start GMAT preparations?

How to Improve Quant Score?

Gmatclub Topic Tags

Check out my GMAT debrief

How to Solve :

Statistics || Reflection of a line || Remainder Problems || Inequalities