The price of petrol increased by 12 percent last year now, theprices are reduced by 12 percent. Find the net increase and decrease in the price of petrol.
Answers
Answer:
There is a net decrease of 1.44% in the price of petrol.
Step-by-step explanation:
Let the original price of petrol = x
When the price is increased by 12%, the revised price is
x + 12% of x
= x + 0.12x
= 1.12x
Now this price is reduced by 12%. The new price will be:
1.12x - (12% of 1.12x)
= 1.12x - (0.12*1.12x)
= 1.12x - 0.1344x
= 0.9856x
Thus the final price of petrol is 0.9856 times the original price
Final price = 0.9856x
= (1 - 0.0144)*x
= x - 0.0144*x
= x - 1.44% of x
Thus the final price is 1.44% less than the original price. This means that the price has decreased by 1.44%
Alternative method
Concepts used:
1. If the price of an item has decreased by a%, it means that the new price is
(100-a)% of the original price.
2. a% = 0.01*a
Original price = x
Revised price after 12% increase = 1.12x
Final price after 12% decrease = 88% of revised price = 0.88*1.12x
= 0.9856x
= 98.56% of original price
=> decrease of (100-98.56)% or 1.44%
Answer:
Step-by-step explanation: