Mastering Exponential Growth and Decay Calculations

1. A bacteria culture doubles in size every 3 hours. If the initial population is 500, how many bacteria will there be after 12 hours?

• 8000

• 2000

• 4000

• 16000

2. The value of a car decreases by 20% each year. If the car is currently worth $15,000, what will its value be after 3 years?

• $7,680

• $12,000

• $9,600

• $10,000

3. A certain investment grows exponentially at a rate of 5% per year. If you invest $1,000, how much will it be worth after 10 years?

• 1200.00

• 2000.00

• 1628.89

• 1500.50

5. A radioactive substance decays at a rate of 3% per year. If you start with 200 grams, how much will remain after 5 years?

• 180 grams

• 150 grams

• 171.75 grams

• 200 grams

6. A bank offers an account that compounds interest annually at a rate of 6%. If you deposit $2,000, how much will you have after 5 years?

• 3000.00

• 2800.50

• 2676.45

• 2500.00

7. The number of users of a new app is modeled by the function N(t) = 200(1.5)^t, where t is the number of months since launch. How many users will there be after 4 months?

• 600

• 1500

• 1013

• 800

8. A tree grows at a rate of 10% per year. If its current height is 2 meters, what will its height be after 3 years?

• 3.0 meters

• 2.5 meters

• 2.0 meters

• 2.662 meters

9. A population of fish in a lake is modeled by the equation P(t) = 300e^(0.1t). How many fish will there be after 10 years?

• 1000

• 500

• 650

• 815

10. A certain type of investment triples every 5 years. If you invest $500, how much will you have after 15 years?

• 4500

• 27000

• 9000

• 13500