Exponential Models Test – Algebra 2 Math (Printable PDF)

Question 1 Reading a model (2 points)

A stock fund’s value is modeled by f(t) = 640(0.92)^t, with t in years.

1. State the initial value and the percent change per year. (1 point)
2. Find f(4) to the nearest cent. (1 point)

Question 2 Compound interest (3 points)

A deposit of $3,200 earns 3.8% compounded quarterly. Write the model and find the balance after 9 years.

Question 3 Continuous compounding (3 points)

A deposit of $5,000 earns 4% interest.

1. Find the balance after 12 years with continuous compounding. (2 points)
2. How much more is that than with annual compounding? (1 point)

Question 4 Half-life (3 points)

A 240-gram sample has a half-life of 8 hours. The graph is shown.

1. Write the model N(t). (1 point)
2. How many grams remain after 24 hours? (1 point)
3. How many grams remain after 4 hours, to the nearest tenth? (1 point)

Question 5 Doubling followers (3 points)

A club’s social media account has 1,800 followers and the count doubles every 4 days.

1. Write a model for the number of followers after t days. (1 point)
2. Find the number of followers after 12 days. (1 point)
3. Find the number after 2 days, to the nearest follower. (1 point)

Question 6 Interpreting parameters (2 points)

A leased truck’s value is V(t) = 28,000(0.85)^t dollars after t years. State the meaning of 28,000 and of 0.85, and find the value after 2 years.

Question 7 Model from a table (2 points)

A savings balance is shown in the table. Decide whether the growth is exponential, state the percent growth per year, and write the model.

Question 8 Decay from a graph (2 points)

The graph of an exponential decay function y = a · b^t is shown.

1. Write the equation. (1 point)
2. Find y when t = 3. (1 point)