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3. Increase Percentage Change A computer accessories shop increased the price of one of its printers from £80 to £100. Find the percentage increase in price. £100 £80 Original PriceNew Price Percentage change = change original quantity x 100 In this case the change is an increase. Percentage increase = increase original quantity x 100 Percentage increase = 20 80 x 100 = 25%

4. £260 £250 Original PriceNew Price A computer accessories shop increased the price of one of its “All in one” printers from £250 to £260. Find the percentage increase in price. Percentage change = change original quantity x 100 Percentage increase = 10 250 x 100 = 4% Percentage Change

5. £540 £490 Original PriceNew Price Percentage Change Find the percentage increase in price of the sideboard. (1 dp) Percentage change = change original quantity x 100 Percentage increase = 50 490 x 100 = 10.2%

6. Percentage Change 0 -10 -20 -30 10 20 30 40 50 60 oCoC 8:30 0 -10 -20 -30 10 20 30 40 50 60 oCoC 12:00 The temperature readings for morning and noon at Bristol are shown on the thermometers. Calculate the percentage increase in temperature between these times. Percentage increase = 10 20 x 100 = 50%

7. The items below show the old price and new price after an increase. Calculate the percentage increase in price in each case. ( 1 dp ) £330 £640 £98 £24 £8.10 £50 £600 £300 £90 £6.20 £44 £20 8 90 x 100 = 8.9% 40 600 x 100 = 6.7% 30 300 x 100 = 10% 4 20 x 100 = 20% 1.90 6.20 x 100 = 30.6% 6 44 x 100 = 13.6% Percentage Change

8. Decrease A computer accessories shop reduced all its prices in a sale. Simon bought a printer in the sale for £90. What was the percentage decrease in price? £90 £100 Original PriceSale Price Sale Percentage change = change original quantity x 100 In this case the change is a decrease. Percentage decrease = decrease original quantity x 100 Percentage decrease = 10 100 x 100 = 10% Percentage Change

9. A computer accessories shop reduced all its prices in a sale. Jenny bought a printer at the sale price. What was her percentage saving? Original PriceSale Price Sale Percentage change = change original quantity x 100 Percentage decrease = decrease original quantity x 100 Percentage decrease = 60 260 x 100 = 23.1% £200 £260 Percentage Change So Jenny made a 23.1% saving

10. £475 £540 Original PriceSale Price Percentage Change Find the percentage decrease in cost of the sideboard in the furniture sale. (1 dp) Percentage change = change original quantity x 100 Percentage decrease = 65 540 x 100 = 12.0% Sale

11. Original Price Sale Price Percentage Change Find the percentage decrease in the cost of the car in the sale. (1 dp) Percentage change = change original quantity x 100 Percentage decrease = 1500 35 500 x 100 = 4.2% Sale £34000 £35500

12. Percentage Change 0 -10 -20 -30 10 20 30 40 50 60 oCoC 1200 0 -10 -20 -30 10 20 30 40 50 60 oCoC 0200 The temperature readings for the times shown in Cairo are displayed on the thermometers. Calculate the percentage decrease in temperature between these times. Percentage decrease = 10 40 x 100 = 25%

13. Calculate the percentage decrease in prices for each of the items shown in the sale. (I dp) £330 £620 £85 £18 £8.10 £48 £700 £350 £105 £10.00 £54 £20 20 105 x 100 = 19.0% 80 700 x 100 = 11.4% 20 350 x 100 = 5.7% 2 20 x 100 = 10% 1.90 10.00 x 100 = 19% 6 54 x 100 = 11.1% Percentage Change Sale

14. 19501980% increase/decrease A13.714.2 B9.69.1 C47.855.6 D24.622.4 E5.77.5 The table below shows the populations of 5 countries in both 1950 and 1980 (in millions). Calculate the percentage increase/decrease in each case. (1 dp) 3.6% increase 5.2% decrease 16.3% increase 8.9% decrease 31.6% increase Population change

15. Worksheet1 The items below show the old price and new price after an increase. Calculate the percentage increase in price in each case. ( 1 dp ) £330 £640 £98 £24 £8.10 £50 £600 £300 £90 £6.20 £44 £20 Percentage Change

16. Worksheet 2 Calculate the percentage decrease in prices for each of the items shown in the sale. (I dp) £330 £620 £85 £18 £8.10 £48 £700 £350 £105 £10.00 £54 £20 Percentage Change Sale