2.7 Percent of Change

1. 2.7 Percent of Change Sale Price and Discount Dave Wesley and Ed Judd

2. Percent of Increase or Decrease • Amount of Change Original Amount If Mr. Wesley has 20 students this period and 25 students next period, what is the percent of change?

3. Percent of Increase or Decrease • Amount of Change Original Amount If Mr. Wesley has 20 students this period and 25 students next period, what is the percent of change? • 25 – 20 Amount Change 20 Original Amount

4. Percent of Increase or Decrease • Amount of Change Original Amount If Mr. Wesley has 20 students this period and 25 students next period, what is the percent of change? 25 – 20 20 5/20 = .25 = 25% increase

5. Percent of Increase or Decrease • Amount of Change Original Amount • If Mr. Judd has 20 students this period and 5 students next period, what is the percent of change?

6. Percent of Increase or Decrease • Amount of Change Original Amount • If Mr. Judd has 20 students this period and 5 students next period, what is the percent of change? • 20 – 5 Amount Change 20 Original Amount

7. Percent of Increase or Decrease • Amount of Change Original Amount • If Mr. Judd has 20 students this period and 5 students next period, what is the percent of change? • 20 – 5 Amount Change 20 Original Amount • 15/20 = .75 = 75% decrease

8. Percent of Change • If a wrestler weighs 110 pounds, what is his percent of increase to move up to the 112 pound weight class or what is his percent of decrease to move down to the 103 pound weight class?

9. Percent of Increase • If a wrestler weighs 110 pounds, what is his percent of increase to move up to the 112 pound weight class or his percent of decrease to move down to the 103 pound weight class? To move up, he must gain 2 pounds. 112-110 = 2 = 0.018 110 110 (rounded to the nearest thousandth)

10. Percent of Increase • If a wrestler weighs 110 pounds, what is his percent of increase to move up to the 112-116 pound weight class or his percent of decrease to move down to the 103-107 pound weight class? To move up, he must gain 2 pounds. 2/110 = .018 = 1.8 % increase (rounded to the nearest tenth of a percent.)

11. Percent of Decrease • If a wrestler weighs 110 pounds, what is his percent of increase to move up to the 112 pound weight class or his percent of decrease to move down to the 103 pound weight class? To move down, he must lose 3 pounds. 110-103 = 7 = 0.064 110 110 (rounded to the nearest thousandth)

12. Percent of Decrease • If a wrestler weighs 110 pounds, what is his percent of increase to move up to the 112 pound weight class or his percent of decrease to move down to the 103 pound weight class? To move down, he must lose 7 pounds. 7/110 = .064 = 6.4 % decrease (rounded to the nearest tenth of a percent.)

13. PercentIncrease or Decrease Percent of Decrease New car $17,000 Value now $13,500

14. PercentIncrease or Decrease Percent of Decrease New car $17,000 Value now $13,500 Amount change: 3,500 Original Amount: 17,000 0.206 = 20.6% (nearest tenth %)

15. PercentIncrease or Decrease Percent of Increase Baseball card $3 Value now $9

16. PercentIncrease or Decrease Percent of Increase Baseball card $3 Value now $9 Amount change: 6 Original Amount: 3 2.00 What is this as a percent?

17. Sale Price and Discount

19. How to find the sales tax! • First find out what tax rate you will be paying. • In California the tax rate is 8.25%! • Convert your percentage to a decimal by moving your decimal two spaces to the left. Ex. 8.25% =.0825 (Don’t forget to add a zero) • Multiply the decimal form of the tax rate by the price of the item you are purchasing. Ex. .0825 x $ cost of the item

20. How to find the sales tax! • So if an item costs $5.00 • Sales tax is 8.25% • Convert 8.25% to .0825 • So .0825 x $5 = $.41 • The sales tax is $.41 • But the total price of the item is $5.00 + $.41 =$5.41

21. How to find the Discount & Discounted Price • Find out the % of the discount. Convert the % to a decimal. • Multiply the decimal by the original price. • Take the answer in step 2 and subtract it from the original price. Example • Discount 20% = .20, • $10 x .20 = $2.00 • $10.00 - $2.00 = $8.00

22. Hollister Shirt $10The tax is 8.25% • 1. How much would you spend on taxes for this shirt? • $.83 • 2. What would be the total cost of this shirt? • $10.83

23. $45.00 iPod shuffle 1GBtax rate = 8.25% 3. What will the sales tax be if you purchase this item? $3.71 4. What will the total price be if you purchase this item? $48.71

24. E-matic 4GB Video MP3 Player with 2.4" Screen, Camera and Video Recorder $49.00 Tax rate 8.25% • 5. What will be the total of the state sales tax? • $4.04 • 6. What will be the total price of the MP3 Player after the state tax of 8.25% is applied? • $53.04

25. Xbox 360 for $199.99 • The Discount is 25% • 9. What is the discount? • $ 50.00 • 10. What is the price after the discount? • $149.99 • 11. What is the price after the discount and after taxes? • $162.36

26. Ipod Touch for $229.99 • The tax rate is 4% • 12. What is the tax? • $ 9.20 • 13. What is the total price after taxes? • $239.19

27. Discount and Sale Price • Lets say you are going to purchase a $95 graphing calculator. You are able to get a 20% discount and must pay 7.5% sale tax. Stop doing this the long way! An algebraic shortcut to find your total cost is much Easier and saves time! Are you ready………….

28. Discount and Sale Price Calculator $95 x (.80) = $76

29. Total Price with Tax Calculator $76 x (1.075) = $81.70 +

30. Total Price with Tax Calculator x Cost Percentage x Total Tax $95 x (.80) x (1.075) = $81.70 Final cost with discount And tax included! Easy Game………………..