The ratio of sum of interior angles to sum of exterior angles of a regular polygon of n sides is \frac{7}{2}. What is the measure of an interior angle of polygon?
- A. 110^\circ
- B. 120^\circ
- C. 130^\circ
- D. 140^\circ ✓
Correct Answer: D. 140^\circ
Explanation
The sum of exterior angles of any polygon is 360^\circ. The sum of interior angles is \frac{7}{2} \times 360^\circ = 1260^\circ. For a regular n-gon, (n-2) \times 180^\circ = 1260^\circ \implies n=9. Each interior angle is \frac{1260^\circ}{9} = 140^\circ.
Related questions on Geometry
- In a triangle ABC, \angle A = 30^\circ, AB = 7 cm and AC = 12 cm. What is the area of the triangle ABC?
- ABC is a triangle right angled at B. D is a point on AC such that BD is perpendicular to AC. If AB = p and BC = \sqrt{3}p, then what is BD...
- The difference between an interior angle and an exterior angle of a regular polygon is 120°. What is the number of sides of the polygon?
- An angle q is exactly one-fourth of its complementary angle. What is the value of angle q?
- The sides of a triangle are 11 cm, 60 cm and 61 cm. What is the area of the triangle formed by joining the mid-points of the sides of the tr...