1. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 1 Percent 7

2. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 2 R.1 Fractions 1.Find sales tax and total cost. 2.Estimate and calculate restaurant tips. 3.Find the discount and sale price. 4.Calculate simple interest and the total amount due on a loan. Objectives 7.5 Consumer Applications: Sales Tax, Tips, Discounts, and Simple Interest

3. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 3 Find sales tax and total cost.

4. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 4 Find sales tax and total cost. Example Step 1 Read the problem. It asks for the sales tax on a Blue-ray player and the total cost. Step 2 Assign a variable. Let n be the amount of tax. Suppose that you buy a Blu-ray player for $289 from A-1 Electronics. The sales tax rate in your state is How much is the tax? What is the total cost of the Blue-ray player?

5. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 5 Example (continued) Step 3 Write an equation. Use the percent equation. Step 4 Solve. Find sales tax and total cost.

6. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 6 Example (continued) Step 5 State the answer. The tax is $18.79 and the total cost of the DVD player, including tax, is $307.79. Step 6 Check. Round $289 to $300. 1% of $300 is $3. Round to 7%. 7% would be 7 times $3 or $21 for sales tax. Our solution of $18.79 is close to $21, so it is reasonable. Find sales tax and total cost.

7. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 7 Find sales tax and total cost. Example Step 1 Read the problem. It asks for the sales tax rate on a car purchase. Step 2 Assign a variable. Let p be the tax rate. Ms. Ortiz bought a $28,950 hybrid car. She paid an additional $2171.25 in sales tax. What was the sales tax rate?

8. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 8 Example (continued) Step 3 Write an equation. Use the percent equation. Step 4 Solve. Find sales tax and total cost.

9. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 9 Example (continued) Step 5 State the answer. The sales tax rate is 7.5%. Step 6 Check. If the tax rate was 1%, then 1% of $28,950 is $289.50, or about $300. Round 7.5% to 8%. Then 8% would be 8 times $300, or $2400. The tax amount given in the original problem, is close to the estimate, so our solution of 7.5% is reasonable. Find sales tax and total cost.

10. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 10 Estimate and calculate restaurant tips. Example Estimate: Round $77.85 to $80. 10% of $80 is $8. 20% of $80 would be 2 times $8 or $16. Kirby took his wife to dinner at a nice restaurant to celebrate her promotion at work. The bill came to $77.85. How much should he leave for a 20% tip? Estimate then find the exact amount.

11. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 11 Example (continued) Exact: 20% of $77.85 is $15.57 which is close to the estimate of $16. Estimate and calculate restaurant tips.

12. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 12 Example Estimate: Round $21.63 to $20. 10% of $20 is $2. 5% of $20 would be half $2 or $1. So an estimate of the 15% tip would be $2 + $1 = $3. An estimate of the amount each woman should pay is ($20 + $3) ÷ 3 ≈ $8. Linda, Peggy, and Mary ordered similarly priced lunches and agreed to split the bill plus a 15% tip. How much should each woman pay if the bill is $21.63? Estimate and calculate restaurant tips.

13. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 13 Example (continued) Exact: The tip is approximately $3.24. Total cost: $21.63 + $3.24 = $24.87 Cost each: $24.87 ÷ 3 = $8.29 Estimate and calculate restaurant tips.

14. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 14 Find the discount and sale price.

15. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 15 Example Step 1 Read the problem. It asks for the sale price on a dining room set. Step 2 Assign a variable. Let n be the amount of discount. The Oak Mill Furniture Store has an oak dining room set with an original price of $840 on sale at 15% off. Find the sale price. Find the discount and sale price.

16. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 16 Example (continued) Step 3 Write an equation. Use a form of the percent equation. Step 4 Solve. Find the discount and sale price.

17. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 17 Example (continued) Step 5 State the answer. During the sale, you can buy the dining room set for $714. Step 6 Check. Round $840 to $800. 10% of $800 is $80 and 5% is half as much, or $40. So 15% of $800 is $80 + $40 = $120. An estimate of the sale price is $800 – $120 = $680, so the exact answer of $714 is reasonable. Find the discount and sale price.

18. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 18 Calculate simple interest and the total amount due on a loan. Interest is a fee paid, or a charge made, for lending or borrowing money. The amount of money borrowed is called the principal. The charge for interest is usually given as a percent, called the interest rate. In most cases, interest is calculated on the original principal and is called simple interest.

19. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 19 Calculate simple interest and the total amount due on a loan.

20. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 20 Example The interest is $120. Find the simple interest and total amount due on a $2000 loan at 6% for 1 year. Calculate simple interest and the total amount due on a loan. The total amount due is $2120.

21. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 21 Example The interest is $1249.50. Find the simple interest and total amount due on a $4200 loan at for years. Calculate simple interest and the total amount due on a loan. The total amount due is $5449.50.

22. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 22 Example Find the simple interest and total amount due on $840 at for 7 months. Calculate simple interest and the total amount due on a loan. The time is of a year. Use the formula

23. Copyright © 2014, 2010, 2007 Pearson Education, Inc. Slide 23 Example The interest is $47.78. rounded to the nearest cent. (continued) Calculate simple interest and the total amount due on a loan. The total amount due is $840 + $47.78 = $887.78.