In a triangle PQR, PQ = PR and ∠Q is twice that of ∠P.

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In a triangle PQR, PQ = PR and ∠Q is twice that of ∠P. Then ∠Q is equal to

1. 72°
2. 36°
3. 144°
4. 108°

Correct Option: A

On the basis of question we draw a figure of triangle PQR ,

PQ = PR
∴ ∠PQR is an isosceles triangle.
∴ ∠PQR = ∠PRQ and ∠PQR = 2∠QPR
In ∆ PQR,
We know that ,∠P + ∠Q + ∠R = 180°

⇒	∠Q	+ ∠Q + ∠Q = 180°
	2

⇒	5	∠Q = 180°
	2

∴ ∠Q =	180° × 2	= 72°
	5