Answer
$m$ of the interior angles in a $40$-gon = $6840^{\circ}$
Work Step by Step
According to the Polygon Angle-Sum Theorem, the sum of all the measures of the interior angles of a polygon is $(n - 2)180$, where $n$ is the number of sides of the polygon.
We have a polygon that has $40$ sides.
$m$ of the interior angles in a $40$-gon = $(40 - 2)180$
Evaluate what is in parentheses first, according to order of operations:
$m$ of the interior angles in a $40$-gon = $(38)180$
Multiply to solve:
$m$ of the interior angles in a $40$-gon = $6840^{\circ}$
