If the length of a rectangle is increased by 10% and its width is increased by 25%, what is the percentage increase in its area?

Explanation

Let the original length and breadth be 100 units each, so the original area is 100 × 100 = 10,000 square units. After increasing length by 10%, it becomes 110 units, and after increasing breadth by 25%, it becomes 125 units. The new area is 110 × 125 = 13,750 square units. The increase in area is 13,750 - 10,000 = 3,750 units, which corresponds to a 37.5% increase over the original area.