Question

Find the number of sides of a polygon whose sum of interior angles is 9 right angles.

• A. 5
• B. 10
• C. 6
• D. No such polygon exist.

Answer 1

The correct option is D

No such polygon exist.

Let the number of sides be n

$\therefore$ The sum of its interior angles

$=(2n-4)\times {90}^{\circ }$

According to the given condition

$(2n-4)\times {90}^{\circ }=9\times {90}^{\circ }$

$\Rightarrow 2n-4=9$

$\Rightarrow 2n=9+4=13$

$\Rightarrow n=6.5$

Hence no such polygon exist whose sum of interior angles is equal to 9 right angles.