Question

The sum of all the interior angles of a decagon is ___.

• A. 1000${}^{\circ }$
• B. 960${}^{\circ }$
• C. 1440${}^{\circ }$
• D. 1200${}^{\circ }$

Answer 1

The correct option is C

1440${}^{\circ }$

A decagon is a polygon having 10 sides.

$\because$ The sum of interior angles of a polygon having 'n' sides is (2n- 4) $\times$ 90${}^{\circ }$.

$\therefore$ sum of interior angles of a decagon= (20 - 4) $\times$ 90${}^{\circ }$

= 16 $\times$ 90${}^{\circ }$

= 1440${}^{\circ }$