In the figure, sides QP and RQ of ΔPQR are produced to points S and T respectively. If ∠SPR=135° and ∠PQT=110°, find ∠PRQ.

Given, ∠SPR=135°,∠PQT=110°
According to the question
∠SPR+∠QPR=180° (SQ is a straight line)
⇒135°+∠QPR=180°
⇒∠QPR=45°
Also
∠PQT+∠PQR=180° (TR is a straight line)
⇒110°+∠PQR=180°
⇒∠PQR=70°
Now,
∠PQR+∠QPR+∠PRQ=180° (Sum of the interior angles of the triangle)
70°+45°+∠PRQ=180°
⇒115°+∠PRQ=180°
⇒∠PRQ=65°