1. Planning Ahead Saving money is an important part of financial freedom and responsibility. What are the advantages of having a savings account?

2. compound interest table A tool to calculate compound interest quickly. Lesson Objective Find compound interest using a table and the compound interest formula. Content Vocabulary compound interest table

4. State Bank pays 6 percent interest compounded quarterly on regular savings accounts. You deposited $3,000 for 2 years. You made no deposits or withdrawals. How much interest did you earn in 2 years? (Note: Use the Compound table on page A11 of your textbook to solve this problem.) Example 1

5. Find the total interest periods. Periods per Year × Number of Years 4 quarters per year × 2 years = 8 periods Example 1 Answer: Step 1

6. Find the interest rate per period. Periods per Year × Number of Years Annual Rate ÷ Number of Periods per Year 6% ÷ 4 = 1.5% Example 1 Answer: Step 2

7. Find the amount for 8 periods at 1.5 percent per period using the Compound Interest Amount of $1.00 table on page A11 of your textbook. It is 1.12649. Example 1 Answer: Step 3

8. Find the amount. Original Principal × Amount of $1.00 $3,000.00 × 1.12649 = $3,379.47 Example 1 Answer: Step 4

9. Find the compound interest. Amount – Original Principal $3,379.47 – $3,000.00 = $379.47 Example 1 Answer: Step 5

10. Juan Lopez opens an account and deposits $4,379.47. The account pays 6 percent annual interest and compounds quarterly. Six months later he deposits $2,000. How much will he have in the account in 1½ more years if he continues to pay 6 percent interest compounded quarterly? Example 2

11. Find the total interest periods for first 6 months. Periods per Year × Number of Years 4 quarters per year × ½ year = 2 periods Example 2 Answer: Step 1

12. Find the interest rate per period. Annual Rate ÷ Number of Periods per Year 6% ÷ 4 = 1.5% Example 2 Answer: Step 2

13. Find the amount of $1.00 for 2 periods at 1.5 percent per period using the Compound InterestAmount of $1.00 table on page 797. It is 1.03023. Example 2 Answer: Step 3

14. Find the amount for 6 months. Original Principal × Amount of $1.00 $4,379.47 × 1.03023 = $4,511.86 (new principal) Example 2 Answer: Step 4

15. Find the amount for 1.5 years. Periods per Year × Number of Years 4 quarters per year × 1.5 years = 6 periods Example 2 Answer: Step 5

16. Find the amount of $1.00 for 6 periods at 1.5 percent per paid using the Compound InterestAmount of $1.00 table on page 797. It is 1.09344. Example 2 Answer: Step 6

17. Find the amount for 1.5 years. New Principal × Amount of $1.00 ($4,511.86 + $2,000.00) × 1.09344 = $6,511.86 × 1.09344 = $7,120.33 Example 2 Answer: Step 7

18. $8,240 invested at 5.75 percent compounded semiannually for 3 years. No additional deposits or withdrawals. Find the amount. Practice 1

19. $8,240 x 1.18538 = $9,767.53 Practice 1 Answer

20. $1,900 invested at 6.25 percent compounded semiannually for 5 years. No additional deposits or withdrawals. Find the amount. How much interest did the money earn in 5 years? Practice 2

21. $1,900 invested at 6.25 percent compounded semiannually for 5 years: 1,900 x 1.36032 = $2,584.61 Interest earned in 5 years: 2,584.61 – 1900 = 2,584.61 – 1900 = $684.61 Practice 2 Answer