The price of fuel decreases by 40%, 60% and 60% in three successive months, but increases by 70% in the fourth month. What is the percentage increase or decrease in the price of fuel in the fourth month as compared to its original price?8597

Correct option is D

Given
Successive decreases = 40%, 60%, 60%
Successive increase = 70%
Formula Used
Final Value = Initial Value $$\times (1 \pm \frac{Rate}{100})$$​​
Solution
Let the initial price of fuel be 100.
Price after 1st month (40% decrease) = 100 $$\times$$​ 0.60 = 60
Price after 2nd month (60% decrease) = 60$$\times$$​0.40 = 24
Price after 3rd month (60% decrease) = 24$$\times$$​ 0.40 = 9.6
Price after 4th month (70% increase) = 9.6 $$\times$$​1.70 = 16.32
Overall decrease = 100 - 16.32 = 83.68
Percentage decrease = 83.68%
Final Answer
So the correct answer is (d)
Exam Hall Method: