Petrol prices rise by 25%. By what percentage must a car owner cut consumption to avoid increasing expenditure?
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Answer: D. 20 %
Explanation
Maintaining constant expenditure despite a price increase requires reducing consumption inversely to the new total cost. A twenty-five percent price increase scales the original cost factor up to one hundred twenty-five percent. Dividing twenty-five by one hundred twenty-five and multiplying by one hundred yields a twenty percent reduction. Constant expenditure rules require that the product of price and consumption remains fixed across price fluctuations. Inverse percentage formulas determine required consumption cuts when commodity prices experience sudden inflationary surges. Percentages represent proportional parts per hundred, facilitating clear comparison of price and consumption changes.
Commuters adjust monthly fuel consumption quantities when global crude oil price hikes increase gasoline costs. Household budget managers reduce electricity usage quantities when utility companies implement seasonal rate tariff increases. Procurement officers scale back raw material purchase volumes when supplier price inflation threatens departmental budgets. Option A suggests twenty-five percent which would fail to offset the price increase and would raise expenditure. Option B suggests thirty percent which represents an excessive consumption cut exceeding required mathematical balance. Option C suggests fifty percent which severely overcorrects for a moderate twenty-five percent price hike.
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- Mathematics
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- Mathematics
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