The price (per litre) of petrol increases by 50%. By what percent should its consumption be reduced such that the expenditure on it increases by 32% only?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 12%.
Original expenditure = P × Q
New price = 1.5P
Let new consumption = xQ
New expenditure = 1.5P × xQ = 1.32PQ
⇒ 1.5x = 1.32
⇒ x = 0.88
Percentage reduction = (1 - 0.88) × 100 = 12%