Question 877404
A rectangle has a perimeter of 140cm. The length of the rectangle is three times the width. Find the difference between the length and the width.
perimeter of rectangle =2(l+b) =140
(l+b) = 70
as per given condition  l=3b  by substituting 
3b +b =70
4b =70 
b=70/4
b=  17.5
L= 3x17.5 =52.5 
l-b= 35 answer