Maths
posted by san .
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 .

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 
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 
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