The sum of the interior angles of a polygon is 20 right angles. How many sides does the polygon have?
A
12
B
20
C
40
D
10
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
The formula for the sum of the interior angles of a regular polygon = (2n - 4) x 90^\circ
Given: Sum = 20 right angles
(2n - 4) x 90^\circ = 20 \times 90^\circ
⇒ 2n - 4 = 20
2n = 24; n = 12.
Source: Myschool Past Questions Archive (Record #3378)