The lenght and the width of a rectangle are in the ratio 3:2. If the lenght is increased by 20 and the width is decreased by 5, the ratio of the lenght to the width becomes 2:1. Find the lenght and width of this rectangle.
l/w=3/2
or w=2l/3
(l+20)/(w-5)=2
l+20=2w-10
l+20=4l/3 -10
1/3 l=30
l=90
w=60