Question 82
The ratio of an interior angle to its corresponding exterior angle of a regular polygon is 9 : 2. If number of sides in the polygon is n, then select the CORRECT option.
Solution
Option B and D are both correct. The sum of interior and exterior angles is 180. Since the ratio is 9:2, let the exterior angle be 9x, and the interior angle be 2x.
$$11x=180$$
$$x=\frac{180}{11}$$
The exterior angle of a regular polygon is 360/n. The derived exterior angle from the x value is 360/11.
So, the n value is 11.
So option B, D are correct.
