Question

The price of fuel decreases by 15%, 40% and 60% in three successive months, but increases by 45% 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. Increases by 73.26%
• B. Increases by 68.39%
• C. Decreases by 70.42%
• D. Decreases by 76.46%

Answer 1

Answer:

C. Decreases by 70.42%

Assume original price = 100

---

Step 1: Apply successive changes

• After 15% decrease:
  
  $100 \times 0.85 = 85$
  

• After 40% decrease:
  $85 \times 0.60 = 51$
  

• After 60% decrease:
  $51 \times 0.40 = 20.4$
  

• After 45% increase:
  $20.4 \times 1.45 = 29.58$
  

  Compare with original

Original = 100
Final = 29.58

Change:
$100 - 29.58 = 70.42 \text{ decrease}$

Final Answer: 70.42% decrease