Question P6 Working backwards
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Answer
See all 8 steps
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You know how it ended. Undo each step, last one first.
In this one. Both prices are cut from the same $68, so a $6.80 gap in price is a fixed 10% gap in discount — and because the question never says who paid more, that 10% swings both ways.
Also uses: Units and parts
The question gives the final amount after a sequence of changes and asks what the amount was 'at first' or 'to begin with'.
Children undo the steps in the same order they happened rather than in reverse, or forget that a percentage profit is added to the cost price, so the final price is 120% of it, not 100%.
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