1. Percent Proportions & Equations

2. A percent is a ratio that compares a number to 100. A commission is a percent of the amount of your sales. A percent of change is the percent a quantity increases or decreases from its original amount.

3. Markup is the difference between the selling price and the store’s cost of an item. A discount is the difference between the original price and the sale price of an item.

4. Review: Calculating Percent

5. Write each ratio as a percent: 3/5

6. Answer: 60%

7. Write each ratio as a percent: 1/2

8. Answer: 50%

9. Write each ratio as a percent: 11/20

10. Answer: 55%

11. Write each decimal as a percent: 0.375

12. Answer: 37.5%

13. Write each percent as a decimal: 325.4 %

14. Answer: 3.254

15. Find the answer: 58% of 50

16. Answer: 29

17. Find the answer: 8% of 400

18. Answer: 32

19. Solving problems using percent proportion and by setting up an equation.

20. Percent: n%= n/100 (ratio) What percent of 5000 is 3.8? Setting up a proportion: n/100 = 3.8/5000 n = (3.8/5000) ∙ 100 = 0.08% Setting up as an equation: n ∙ 5000 = 3.8 n = 3.8/5000 = 0.0008 Write as a percent: 0.0008 ∙ 100% = 0.08%

23. Let’s solve problems using percent proportion and by setting up an equation.

24. What is 5% of 19?

25. Answer: Proportion: 5/100 = n/19 Equation: n = 5% ∙ 19 n = 0.95

26. 90% of what is 342?

27. Answer: Proportion: 90/100 = 342/n Equation: 0.9 ∙ n = 342 n = 380

28. 24% of 300 is what?

29. Answer: Proportion: 24/100 = n/300 Equation: 0.24 ∙ 300 = n n = 72

30. Find 320% of 60.

31. Answer: Proportion: 320/100 = n/60 Equation: n = 3.2 ∙ 60 n = 192

32. 45 is 60% of what?

33. Answer: Proportion: 60/100 = 45/n Equation: 45 = 0.60 ∙ n n = 75

34. What percent of $4000 is $64?

35. Answer: Proportion: n/100 = 64/4000 Equation: n ∙ 4000 = 64 (remember to convert the decimal to percent by multiplying by 100%) n = 1.6%

36. Commission, markup, discount, tax, tip, etc.

37. Find the commission: You sold a car for: $30,000 Commission: 3%

38. Answer: Sale price = $30,000 Commission = $30,000 ∙ 0.03 = $900 = $900

39. Find the final price: Cost of a sled: $99.50 Markup: 95%

40. Answer: Cost = $99.50 Markup = 99.50 ∙ 0.95 = $94.53 Final: $99.50 + $94.53 = $194.03

41. Find the final price: Original price of concert tickets: $100.00 Discount: 21%

42. Answer: Cost = $100.00 Discount = 100 ∙ 0.21 = $21.00 Final: $100 - $21 = $79

43. Find the final price: Original cost of book: $49.95 Tax: 3%

44. Answer: Cost = $49.95 Tax = 49.95 ∙ 0.03 = $1.50 Final: $49.95 + $1.50 = $51.45

45. Find the final price: Original cost of meal: $49.95 Tax: 3% Tip: 15%

46. Answer: Cost = $49.95 Tax = 49.95 ∙ 0.03 = $1.50 Cost of meal = $49.95 + $1.5 = $51.45 Tip: $51.45 ∙ 0.15 = $7.72 Final cost = $51.45 + $7.72 =$59.17

47. Percent Change

48. A percent of change is the percent a quantity increases or decreases from its original amount.

49. From a to b. % change = (positive difference)/a Example: From 82 to 38 (82-38)/82 = 0.537 = 53.7% decrease

50. Find the Percent Change. State if it is an increase or decrease. Round answer to the nearest tenth of a percent.

51. From 75 to 45.

52. From 75 to 45 (75-45)/75 = 0.40 = 40% decrease

53. From 33 to 47.

54. From 33 to 47 (47-33)/33 = 0.424 = 42.4% Increase

55. From 92 to 9.7

56. (92-9.7)/92 = 0.895 = 89.5% decrease

57. From 70 to 62

58. (70-62)/70 = 0.114 = 11.4% decrease

59. From 58.5 to 76.3

60. (76.3-58.5)/58.5 = 0.304 = 30.4% increase

61. From 8 to 4

62. (8-4)/8 = 0.5 = 50% decrease

63. Markup is the difference between the selling price and the store’s cost of an item. A discount is the difference between the original price and the sale price of an item.

64. Find the percent markup. $22 marked up to $33

65. From 22 to 33 (33-22)/22 = 0.5 = 50% markup

66. Find the percent markup. $15 marked up to $60

67. From 15 to 60 (60-15)/15 = 3 = 300% markup

68. Find the percent of discount. $9 discounted to $4

69. From $9 to $4 (9-4)/9 = 0.56 = 56% discount

70. Find the percent of discount. $10 discounted to $7

71. From $10 to $7 (10-7)/10 = 0.30 = 30% discount

72. Problems from past test

73. If 8 is 12.5% of x, then x is what percent of 4096? (Round your answer to the nearest whole number.)

74. Answer: 8 = 0.125 ∙ x 64=x 64 = p ∙ 4096 0.0156 = p 1.56% Round = 2%