△ABC and △PQR are similar to each other. If ∠A = 45° and ∠R = 55°; then angle B is equal to :

1. 55°

2. 80°

3. 100°

4. 90°

Since, △ABC and △PQR are similar to each other.

∠P = ∠A = 45°, ∠C = ∠R = 55° and ∠B = ∠Q = x(let).

In △ABC,

By angle sum property of triangle.

⇒ ∠A + ∠B + ∠C = 180°

⇒ 45° + x + 55° = 180°

⇒ x + 100° = 180°

⇒ x = 80°.

∴ B = 80°.

Hence, Option 2 is the correct option.