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

Quant Formula Sheet

How to Solve :

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