Application of Exponential

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x

• y = 15(1.35)^x

• y = 15(0.35)^x

• y = 35(1.15)^x

A new savings account is opened with $400 and gains 3% every year. What is the exponential function?

• f(x)=400(1+3)^x

• f(x)=400(1-0.03)^x

• f(x)=400(1+0.03)^x

• f(x)=400(0.03)^x

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x

• y = 15(1.35)^x

• y = 15(0.35)^x

• y = 35(1.15)^x

The amount of ants in a colony, f, that is decaying can be modeled by                      f(x) = 800(.87)^x, where x is the number of days since the decay started. By what percentage is the colony decaying?

• 87%

• 13%

• 800%

• 8.7%

The population of wolves in a certain place was 5,450 in 2013. Each year the population has decreased by 5%. What equation models the population of wolves since 2013?

• p(x) = 5450 - 95x

• p(x) = 5450(0.05)^x

• p(x) = 5450(0.95)^x

• p(x) = 5450 (1.05)^x

If there is a culture with bacteria growing in it at a continuous rate of 2% per hour, and the starting number of bacteria is 100,000. How much bacteria will there be in 1 day? (round to the nearest whole number)

• 161,607

• 102,020

• 12,151,042

• 122,140

Which formula would be the best for the following question: A town is decreasing in population. It loses population at a rate of 5%, compounded continuously. If the town starts with 200,000 people, how many will it have in 15 years?

Which formula would be the best for the following question: You buy a pair of shoes autographed by Steve Lacy and never wear them. They increase in value 9% a year, compounded monthly, and they were originally worth $600. How much are they worth in 4 years?

Which formula would be the best for the following question:

The number of bacteria in a vial of pond water starts at 100. It continuously increases at a rate of 50% per hour. How many bacteria will there be in 6 hours?

Courtney saved up $2,200 working as a waitress over the summer. She put this money into a bank account that earned 5.2% interest and is compounded daily. How much will she have in her account at the end of 4 years?

• $2201.25

• $2694.55

• $2707.45

• $2708.63