The school hall is 4 times as long as it is wide. If the perimeter is 55m, what is the length? and what is the width?

- - The width of the school is ' W '. We don't know what that is yet,

but we're going to find out.

- - We're told that the length is 4 times as much. So the length is ' 4 W '.

- - Perimeter is (2 widths) + (2 lengths).

2 widths = 2 W

2 lengths = 8 W

Perimeter = 10 W

- - We're also told that the perimeter is 55m. That's just what we need.

10 W = 55 m

Divide each side of this equation by 10:

W = 5.5 m

There's the width!

The length of the hall is 4 times as much.

Length = 4 W = 22 m