Question
If the length of the rectangle is increased by 40%, by
what percent should the width be reduced to maintain the same area?Solution
Let the length = 100 and breadth = 100 Now, new length = 140 and breadth = x So, 100 × 100 = 140 × x x = 500/7 Required % decrease = 100 – 500/7 = 200/7 = 28.57% Alternate Method: Let Length is changing from 100 to 140 So breadth will decrease reversly from 140 to 100 So % decrease = {(140-100)/140} × 100 = 200/7% = 28.57%
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