20*10 = 200
20*3/2 * 10*7/3 = 200 *7/2 = 700
increase = 500
500/200 = 2.5
2.5 * 100 = 250 %
Two sides of rectangle are 20 cm &10 cm. They are increased in ratio 2:3 & 3:7 . Find the percentage increase in its area?
1 answer