The sum of the interior angles of a polygon is 20 right angles. How many sides does the polygon have?
-
12
- 20
- 40
- 10
The correct answer is: A
Explanation
The formula for the sum of the interior angles of a regular polygon = (2n - 4) x 90°
Given: Sum = 20 right angles
(2n - 4) x 90° = 20 \times 90°
⇒ 2n - 4 = 20
2n = 24; n = 12.