If a shop sells a bucket at £16 after a 15% discount, how much would the bucket have been before the discount?
Define the original cost as 100%.
So £16=85% (100-15) of the original cost.
Find 1% of the original cost by dividing both sides by 85.
16/85=85/85%
To find the orginal cost, 100%, multiply both sides by 100.
16/85 * 100 Is the answer.
This is equivilant to multiplying by 100/85 or dividing by 85/100 (as 1/85/100 = 85/100). Once understanding is reached this can be used as a shortcut as follows.
If there has been a 15% discount, divide by 1-0.15. If there has been an increase of 25%, divide by 1+0.25.
AG
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