troop2118 wrote:

Can anyone give me a hint/solution why D is right here?

1: 30+ANGLE Q + ANGLE PRQ = 180 ......................... 1

ANGLE PRS + ANGLE PRQ = 180 ............................... 2

From 1 and 2: Angle PRS - Angle PQR = 30

2: ANGLE PQR + ANGLE PRQ = 150 ......................... 3

ANGLE PRS + ANGLE PRQ = 180 ............................... 4

From 3 and 4: Angle PRS - Angle PQR = 30

So d.

_________________

Verbal: http://gmatclub.com/forum/new-to-the-verbal-forum-please-read-this-first-77546.html

Math: http://gmatclub.com/forum/new-to-the-math-forum-please-read-this-first-77764.html

Gmat: http://gmatclub.com/forum/everything-you-need-to-prepare-for-the-gmat-revised-77983.html

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