Lesson 8 Section two Complete the following questions. Use your notes from lesson 8 – exponential growth and decay. Continue to write your answers on the answer sheet from lesson 8 – section 1. Exponential Growth and Decay GROWTH DECAY When the amount increases by the same percent for each time period A =I(1+r) t When the amount decreases by the same percent for each time period A =I(1-r) t QUESTIONS: 1. What are the formulas for exponential growth and decay? Using the exponential formulas, what does 1 + r or 1 –r become for each problem below?: 2. A $10,000 investment decreased by 3% each year for 5 years. 3. A city population of 200,000 increases 4% each year for 10 years. Complete the following questions below. Decide which formula to use: simple interest, compound interest, exponential growth or decay. 4.Jessica deposits $4,000 in a savings account that pays interest at 6.5% a year. How much will the investment accumulate to after 1 year? 5. $7,563 is invested at 6.2% compounded annually for 10 years. How much money will the investment yield after 10 years? Round to the nearest penny. Find the yield, to the nearest penny, of each investment: 6. A principal of $20,000 is invested at 6% compounded annually for 4 years. 7. A principal of $40,000 is invested at 4.9% compounded annually for 5 years. 8. A principal of $35,000 is invested at 4.5% compounded annually for 4 years. Solve. Round answers to the nearest whole number. 9. A business earned $200,000 in 1997. If it is predicted that the earnings will increase by 3% every year, predict the earnings at the end of 10 years. 10. A biologist discovers that a certain bacteria has a growth rate of 4% every hour. There are currently 15,000 bacteria. Predict the number at the end of 6 hours. • Your homework is a worksheet. Complete all of the problems.