I can do most percentage increase and decrease questions, but I get some wrong. Like this: Pat buys a desk in a '15% off' sale for £57.80 I find 15% of £57.80 and add it back on. I am sure the answer is £66.47 but my teacher says this is wrong. Please explain why. |
What makes this question slightly harder is that you do not know the original price of the item.
The reduction on the item is 15% of the original price.
But you added on 15% of the reduced price instead. That is why your answer is incorrect.
The important part of solving this problem is to relate the price you were given to the original price:
£57.80 is 85% of the original price. |
The correct answer is £68 - have a look at www.percentagecalculator.co.uk for some guidance about working out percentages.