Exponential Functions and Compound Interest

Emily would like to buy some new furniture for her home. She decides to buy the furniture on credit with 9.5% interest compounded quarterly. If she spent $7,400, how much total will she have paid after 8 years. (Round your answer to the nearest hundredth, because it is money.)

Mathematical Equivalence

ON

Emily would like to buy some new furniture for her home. She decides to buy the furniture on credit with 9.5% interest compounded quarterly. If she spent $7,400, how much total will she have paid after 8 years. (Round your answer to the nearest hundredth, because it is money.)

Mathematical Equivalence

ON

Matt earned $475 from mowing lawns last summer. He deposited this money in an account that pays an interest rate of 3.8% compounded annually (n=1). What will be his balance after 15 year?

• $827.52

• $831.10

• $839.45

• $846.80

An investment of $9,875 earns 4.8% interest compounded monthly over 12 years. Approximately how much INTEREST is earned on the investment?

• $7,457.95

• $10,359.57

• $17,546.55

• $484.57

Caiden earned $475 from mowing lawns last summer. He deposited this money in an account that pays an interest rate of 3.8% compounded annually. What will be his balance after 15 years?

• $827.52

• $831.10

• $839.45

• $846.80

Classify the model as Exponential GROWTH or DECAY.
A=1200(.85)⁶

• Growth

• Decay

Classify the model as Exponential GROWTH or DECAY.
A=10(1.01)³

• Growth

• Decay

Write an equation that models the following situation: Samantha's hair was known to grow very rapidly. It began at a length of 6 in and grew at a rate of 14% a week.

• y = 6(0.14)^x

• y = 6(1+14)^x

• y = 6(1.14)^x

• y = 6(0.86)^x

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y = 5000(0.7)^x

• y = 30(5000)^x

• y = 5000(1.3)^x

• y = 5000(0.3)^x

A population growing at an annual rate r will triple in a time t given by the formula A = (1 + r)^t. If the growth rate remains constant and equals 6% per year, about how long will it take the population of the town to triple?

• 18.3 years

• 8 years

• 0.8 years

• 1.8 years