Compound Interest, Compound Continuously, Growth and Decay and Exponential Functions

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

If $400 is invested at 35% interest, compounded continuously, for 2 years, what is the ending balance?

• $280

• $680

• $1,034.47

• $805.50

If $1,000 is invested at 16% interest, compounded continuously, for five years, what is the ending balance?

• $1,225,54

• $2,225.54

• $22,255.40

• $225.54

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

• Growth

• Decay

If you invest $5,000 into an account paying 6% interest compounded continuously, how many years will it take until there is $8,000 in the account?

• 7.83 years

• 6.83 years

• 9.67 years

• 8.67 years

You invest $1600 at an annual interest rate of 4.6% compounded continuously. How much will you have in the account after 4 years.

• $800.26

• $6,701.28

• $10,138.07

• $1,923.23

Which of the following is NOT a characteristic of exponential growth?

• The rate of growth is proportional to the current amount.

• The growth rate remains constant over time.

• The amount increases by a fixed percentage over equal time intervals.

• The amount decreases over time.

If an amount of $1,000 is invested at an annual interest rate of 5% compounded annually, what will be the amount after 2 years?

• Growth

• Decay

Which of the following equations represents an exponential decay function?