Question

The three angles of a quadrilateral are ${76}^0,{54}^0$ and ${108}^0$. Find the measure of the fourth angle.

Answer 1

We know that
Sum of 4 angles of a quadrilateral = ${360}^0$
But sum of 3 angles = ${76}^0+{54}^0+{108}^0$
= ${238}^0$
$\therefore$ 4th angle = 360 - ${238}^0={122}^0$
Hence measure of fourth angle = ${122}^0$