Question
The side of a square is increased by 40%. Find the
percentage change in its area?Solution
Let side of a square be 100. Now, area of a square = 1002 = 10000 If we increase the side of a square by 40%, we get Side = 140% of 100 = 140 New area of square = 1402 = 19600 Difference in Areas = 19600 - 10000 = 9600 Percentage increase = (9600/10000) x 100 = 96% Alternate Method: Successive Increase = 40 + 40 + (40 × 40/100) = 96%
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