Exam 4: Exponential Functions

The price of an item increases due to inflation. Let be the price of the item as a function of time in years, with t = 0 in 2004. What is the daily inflation rate? Round to 2 decimal places.

Kathleen opens a savings account with $1200. The account earns 3.4% annual interest compounded weekly. How much will be in the account after 15 years?

Write a formula that gives the value of an investment which is initially worth $125,000 and loses value at a rate of 2.9% per year.

You invest $6000 in an account earning 2.5% annual interest, compounded continuously. After how many years is the investment worth $14,000? Round your answer to two decimal places, if necessary.

What is the horizontal asymptote of

A population has size 2300 at time t = 0, with t in years. If the population grows by 90 people per year, what is the formula for P, the population at time t?

Assume that all important features are shown in the following graph of . What is ? For or , enter "inf" or "-inf".

The graph below shows the quantity of a drug in a patient's bloodstream over a period of time t, in minutes. Which of the following scenarios best describes the graph?

The population of a city is increasing exponentially. In 2000, the city had a population of 55,000. In 2005, the population was 83,466. The formula for , the population of the town t years after 2000, is given by . Round your second answer to 3 decimal places.

The graph of the exponential function is shown below. The formula for must be .

Is the formula for a function representing a quantity which begins at 2N in year t = 0 and grows at a continuous annual rate of r% given by ?

The population of a city is increasing exponentially. In 2000, the city had a population of 60,000. In 2005, the population was 83,748. Let be the population of the town t years after 2000. Use a graph of to estimate the year in which the population will reach 250,000.

Suppose Taylor win $10,000 in a lottery. If she invests half in a CD earning 4.1% annual interest compounded quarterly and the rest in a savings account earning 3.9% annual interest compounded monthly. How much money does she have after 10 years?

Taylor has $11,000 which she would like to invest. She can either invest in a CD earning 3.1% annual interest compounded quarterly, or she can deposit the money in a savings account earning 2.9% annual interest compounded monthly. If she chooses the investment with the maximum return, how much will she have at the end of 5 years?

What is the maximum effective annual yield among the following three banks? Give your answer correct to four decimal places.

Which of the following characteristics describe the graph of ?

Let give the size of a population of animals in year t. What will the population be after 19 years? Round to the nearest whole number.

A population has size 4900 at time t = 0, with t in years. If the population grows by 15% per year, what is the formula for P, the population at time t?