The cost of Compressed Natural Gas (CNG) per litre is increased by 65%. By what percentage must Manish reduce his consumption of CNG so as not to increase his expenditure? (correct up to two decimal places)
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 39.39%.
Let's assume the original cost of CNG per liter is Rs. 100. After the 65% increase, the new cost becomes Rs. 165.
To maintain the same expenditure, Manish needs to reduce his consumption such that the product of the new cost and new consumption remains the same as the original cost and consumption.
Let's denote the original consumption as 'x' liters.
So, original expenditure = 100 × x = 100x
To maintain the same expenditure with the new cost: 165 × New Consumption = 100x
New Consumption = (100x) / 165 ≈ 0.606x
Therefore, Manish needs to reduce his consumption by approximately 1 - 0.606 = 0.394 or 39.4%.
So, he must reduce his consumption by 39.4% to maintain the same expenditure.