Two angles of a polygon are right angles and the remaining are 120° each. Find the number of sides in it.

Given that a polygon has two right angles and the remaining angles are each 120°, we need to find the number of sides of the polygon, denoted as n.

For a polygon with n sides, the sum of its interior angles is (2n - 4) x 90°.

Accordingly:

⇒ 2 x 90° + (n - 2) x 120° = (2n - 4) x 90°

⇒ 180° + 120°n - 240° = 180°n - 360°

⇒ 120°n - 60° = 180°n - 360°

⇒ 180°n - 120°n = 360° - 60°

⇒ 60°n = 300°

⇒ n = $\dfrac{300°}{60°}$

⇒ n = 5

Hence, the number of sides is 5.