The ribs of a rectangle lie in the ratio 3: 5 and its area is 240 ^ 2cm. Find the perimeter of the rectangle.

Answer 1

Area = (3x)(5x) = 240 cm^2

15x^2 = 240

x^2 = 16

x= 4

It's ribs are 3x =12, 5x=20

Perimeter = 2(12+20) = 2(32) = 64cm