Question

The formula for perimeter is p = 2 l + 2 w. If the perimeter p of a rectangle is 200 mm (millimeters) and the width w = 30 mm, what is l?

A. 60mm
B. 140mm
C. 70mm
D. 100mm

Answer 1

Plug the known variables into the equation.
p=2l+2w
200=2l+2(30)
200=2l+60
140=2l
l=70
The answer is C. 70mm.