Question:
Tick (✓) the correct answer:
The interior angle of a regular polygon exceeds its exterior angle by 108°. How many sides does the polygon have?
(a) 16
(b) 14
(c) 12
(d) 10
Solution:
(d) 10
Each exterior angle of a regular polygon $=\frac{360}{n}$
Each interior angle of a regular polygon $=180-\frac{360}{n}$
$180-\frac{360}{n}-108=\frac{360}{n}$
$\frac{720}{n}=180-108=72$
$n=\frac{720}{72}=10$