Question

The price of fuel decreases by 35%, 10% and 30% in three successive months, but increases by 65% in the fourth month. What is the percentage increase/decrease in the price of fuel in the fourth month as compared to its original price?

• A. Decreases by 33.75%
• B. Decreases by 32.43%
• C. Increases by 31.14%
• D. Increases by 32.84%

Answer 1

Answer:

B. Decreases by 32.43%

Let the original price = 100

Apply successive changes

1st month: ↓35%
$100 \times 0.65 = 65$

2nd month: ↓10%
$65 \times 0.90 = 58.5$

3rd month: ↓30%
$58.5 \times 0.70 = 40.95$

4th month: ↑65%
$40.95 \times 1.65 = 67.5675$

Compare with original

Original = 100
Final ≈ 67.57

Decrease:
$100 - 67.57 = 32.43\%$

Final Answer: 32.43% decrease