Question

The length and breath of a rectangle are 10cm and 8cm.if its length increases by 15%and breath by 20% , find the percentage

increase in its area.

Answer 1

length of new rectangle will be 10 + 15%of10 = 10 + 1.5 = 11.5 cm = L
breadth of new rectangle= 8 + 20% of 8 = 8 + 1.6 = 9.6 cm=B

Area of new rectangle = L*B = 11.5 * 9.6 = 110.4 cm^2

Percentage increased in area :

area of new rectangle - area of old rectangle /area of old rectangle * 100 = 110.4-80/80 * 100 =30.4/80 *100 =38%