The idea
A percentage is a number of parts out of 100. Fractions, decimals and percentages are different ways to show the same proportion.

Follow these steps
- Identify what percentage the given final value represents.
- Scale that value to the percentage required.
- Check whether the answer should be smaller or larger than the starting amount.
original = final ÷ remaining percentage × 100
See the method in action
Example 1
A shop sells 4 identical items for £1020 altogether after reducing each price by 25%. What was the original price of one item?
- Divide the bill by 4: £1020 ÷ 4 = £255.
- Reverse the reduction: £255 ÷ 0.75 = £340.
Example 2
A shop reduces a price by 25%, then reduces the new price by 20%. The final price is £420.00. What was the original price?
- Reverse the second reduction: £420.00 ÷ 0.8 = £525.
- Reverse the first: £525 ÷ 0.75 = £700.
A useful shortcut
For reverse percentages, divide by the percentage represented—not the percentage change.
Watch out for these
Using the final value as 100%
In a reverse problem, the final value represents the percentage left.
Three fresh questions
Ready to check the method? You will get three fresh, validated questions.