Area 7

From Homeworkwiki

Problem: The length and the breadth of a square are increased by 40% and 30% respectively.
What is the percentage increase in the area of the resulting rectangle?

Solution: Let the length of the square be x meters.

After increase by 40%, length becomes 140x/100 m

After increase by 40%, breadth becomes 130x/100 m

∴ Area after change = 140/100x X 130/100x

= 182/100 x² m²

Original area = 1 x² m²

∴ Increase in area = 82/100 x² m²

Percentage increase = 82/100 x² X 1/ x²×100 = 82%