Hi Newaz111,

This DS question is based completely on your knowledge of triangle rules.

We're told that, in triangle PQR, Angle P is 30 degrees MORE than TWICE the measure of Angle Q. We're asked for the measure of Angle R.

Fact 1: PQ = QR

This tells us the the triangle is ISOSCELES, and that Angle P = Angle R. By extension, Angle R is ALSO 30 degrees more than twice the measure of Angle Q.

Thus, our 3 angles are...
P = 30 + 2Q
Q
R = 30 + 2Q

Total = 180 degrees = 60 + 5Q. With this, we can solve for Q, which means we can solve for P and R (the angles end up as Q = 24, P = 78 and R = 78, but that math is unnecessary).
Fact 1 is SUFFICIENT.

Fact 2: Angle P = 78

With this, we can figure out Angle Q. Then, with those 2 angles, we can figure out the remaining angle (Angle R).
Fact 2 is SUFFICIENT

Final Answer: D

GMAT assassins aren't born, they're made,
Rich