The length of a rectangular plot is increased by 25%. To keep it's area uncharged the width of the plot should be___________?
Correct answer: D. Reduced by 20%
- A. Kept unchanged
- B. Increased by 25%
- C. Increased by 20%
- D. Reduced by 20%
Explanation
Let the original length and width be L and W, so the area is LW. After the length becomes 1.25L, the width must be LW ÷ 1.25L = 0.80W, which means a 20% reduction. The likely mistake is option b, increasing both dimensions instead of keeping their product constant.
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About Percentages
Percentages express a quantity as parts per hundred and support calculations involving increases, decreases, discounts, commissions, taxes, and successive changes. Questions require distinguishing percentage change from percentage points and identifying the original value when a final value and its percentage change are given.
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