Growth and Decay: Exploring Exponential Functions

A population of bacteria doubles every 3 hours. If there are initially 500 bacteria, how many will there be after 9 hours?

• 8000

• 2000

• 4000

• 1000

A car's value decreases by 20% each year. If the car is worth $15,000 now, what will its value be after 3 years?

• $7,680

• $12,000

• $10,000

• $5,000

A bank offers an account that compounds interest annually at a rate of 5%. If you deposit $1,000, how much will you have after 5 years?

• 1200.00

• 1500.50

• 1000.00

• 1276.28

A certain species of fish in a lake decreases in population by 10% each year. If there are currently 1,200 fish, how many will be left after 2 years?

• 800

• 1,000

• 1,080

• 972

A tree grows at a rate of 15% per year. If the tree is currently 4 feet tall, how tall will it be after 4 years?

• 8 feet

• 7 feet

• 10 feet

• 5 feet

A radioactive substance decays at a rate of 25% per hour. If you start with 80 grams, how much will remain after 3 hours?

• 50 grams

• 10 grams

• 33.75 grams

• 20 grams

A smartphone's battery life decreases by 30% after each charge. If the battery can hold 100% charge initially, what will be the battery percentage after 4 charges?

• 50%

• 70%

• 10%

• 24.01%

A town's population is 10,000 and is growing at a rate of 8% per year. What will the population be after 5 years?

• 15800

• 13500

• 12000

• 14693

A certain type of plant grows exponentially, increasing its height by 50% every month. If it starts at 2 inches, how tall will it be after 3 months?

• 7 inches

• 5 inches

• 6.75 inches

• 8.5 inches

A loan of $5,000 is taken out with an interest rate of 6% compounded annually. How much will be owed after 4 years?

• 6000.00

• 6312.38

• 5000.00

• 7000.00