Calculate the percentage decrease if the price of petrol goes down from 20cents a litre to 18 cents

Answer 1

To calculate the percentage decrease, the formula is as follows:

Percentage decrease = ((Original price - New price) / Original price) x 100

Plugging in the values:

Percentage decrease = ((20 - 18) / 20) x 100
Percentage decrease = (2 / 20) x 100
Percentage decrease = 0.1 x 100
Percentage decrease = 10%

Therefore, the percentage decrease in price is 10% if the price of petrol goes down from 20 cents a litre to 18 cents.