The ratio of the interior to exterior angle of a regular polygon is 4:1. How many sides does the polygon have?
- 6
- 8
- 12
- 10
Show answer and solution
Correct answer: D. 10
1. Interior + exterior = 180°, and ratio 4:1 means exterior = 180/5 = 36°.
2. Number of sides = 360° / exterior angle = 360 / 36.
3. = 10 sides.
_Source: RRB Group D CEN-02/2018 PYQ, Q.24._