In a △PQR, ∠Q = 50°, ∠R = 65° and QR = 4 cm. Then PQ =

1. 6 cm

2. 5 cm

3. 4 cm

4. 3 cm

In △PQR,

By angle sum property of triangle,

⇒ ∠P + ∠Q + ∠R = 180°

⇒ ∠P + 50° + 65° = 180°

⇒ ∠P + 115° = 180°

⇒ ∠P = 180° - 115°

⇒ ∠P = 65°

Since, ∠P = ∠R = 65°

⇒ PQ = QR = 4 cm (Sides opposite to equal angles in a triangle are equal)

Hence, option 3 is the correct option.