Question

Shane believes that the sum of the

interior angles of an octagon is 1440°.
What mistake did Shane make? How
would you explain the correct solution to
Shane?

Answer 1

The formula for calculating the sum of the interior angles of a polygon is (n - 2) * 180, where n is the number of sides.

Since an octagon has 8 sides, Shane needed to use the formula (8 - 2) * 180 to get 1080.

The only way Shane could have gotten 1440 is by inputting 10 for n since (10 - 2) * 180 = 1440.