Question
The length of a rectangle is increased by 20% and the
width is decreased by 10%. What is the percentage change in the area of the rectangle?Solution
Let length = 100 and width = 100. New length = 120, new width = 90. Original area = 100 × 100 = 10000. New area = 120 × 90 = 10800. Percentage change = [(10800 - 10000) / 10000] × 100 = 8% increase. Answer: a) 8% increase.
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In the given figure CD is parallel to AB then ∠y is?
