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?

Correct option is C

Given:
 Original price of fuel = Rs. 100 (Assumed for calculation)
First month: Decrease by 15%
Second month: Decrease by 40%
Third month: Decrease by 60%
 Fourth month: Increase by 45%
Formula Used:
​$$\text{New Price} = \text{Previous Price} \times \left(1 + \frac{\text{Percentage Change}}{100}\right)$$​​
Solution:
Price after 15% decrease = 100 × (1 - 0.15) = 100 × 0.85 = 85
Price after 40% decrease = 85 × (1 - 0.40) = 85 × 0.60 = 51
Price after 60% decrease = 51 × (1 - 0.60) = 51 × 0.40 = 20.4
Price after 45% increase =20.4 × (1 + 0.45) = 20.4 × 1.45 = 29.58
The price at the end of the fourth month is Rs. 29.58, compared to the original price of Rs. 100.
Percentage Change = $$\left( \frac{29.58 - 100}{100} \right) \times 100 = -70.42\%$$​​