Question

The ratio of the perimeters of two rectangles is 4 to 7. The perimeter of the larger rectangle is 42 inches. What is the perimeter of the smaller rectangle? Please don't just solve it explain it too

Answer 1

The general formula for the perimeter of a rectangle of length l and width w is P=2w+2l.

Let the perimeter of the smaller rectangle be P=2w+2l.
We are told that the perimeter of the larger rectangle is 42.

Thus,

2w+2l 4
----- = ratio of the smaller perimeter to the larger = ---
42 7

Let the smaller perimeter be represented by " p "

Then:
p 4
---- = ---
42 7

Solve for p, and you've got the desired result.