Question

if the ratio of the length to the breadth of a rectangle be 5:3 and its perimeter is 144m, find the length of the rectangle .

Answer 1

Let the length be L. The width W must then be 3L/5, so that the L/W ratio is 5:3.

Also,

Perimeter = 2(L+W) = 144

2L + 2*(3L/5) = (16/5)L = 144
which leads to
L = 45 meters
W = (3/5)L = 27 meters

Answer 2

perimeter: 2L+2B
144=2L+2B

but L/B=5/3 or L=5B/3

then 144=10B/3+2B=16B/3 or B= 3*144/16
solve for B, then L= 5B/3

Answer 3

18