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QMMaths

Reverse percentages

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Answers

    A washing machine goes up in price by 20%, now costing £342.

  1. What decimal would you multiply by to increase a price by 20%?
  2. The old price was multiplied by your answer from to get £342. Think how you would work backwards to get the original price. How much did the washing machine cost before the price change?

    3. A skirt is in a 15% sale and now costs £37.40.

  3. What decimal would you multiply by to decrease a price by 15%?
  4. The old price was multiplied by your answer from (a) to get £37.40. Think how you would work backwards to get the original price. What did the skirt cost before the sale began?

    5. Answer the following using the same technique as above.

  5. If my salary increases by 15% and I now earn £1380 per month, what was my monthly salary before the increase?
  6. If my weight drops to 51.6 kg due to illness and my weight has fallen by 14%, what did I weigh before?
  7. If my daughter’s height increases by 5% to 151.2 cm, how tall was she before her growth spurt?
  8. If I lose 9% of my £2093 savings on tax, what were my savings worth before tax?