Exponential Growth Models: Real-World Challenges for 9th Graders

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

• 3000

• 1000

• 2000

• 4000

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

• $12,000

• $5,000

• $7,680

• $10,000

A tree grows at a rate of 5% per year. If the tree is currently 10 feet tall, how tall will it be after 4 years?

• 12.16 feet

• 15 feet

• 11 feet

• 10.5 feet

A certain investment grows at an annual rate of 8%. If you invest $1,000, how much will it be worth after 5 years?

• 2000.00

• 1200.00

• 1000.00

• 1469.33

A certain species of fish in a lake grows at a rate of 15% per year. If there are currently 200 fish, how many will there be after 2 years?

• 150

• 265

• 230

• 300

A savings account earns interest at a rate of 6% compounded annually. If you deposit $2,000, how much will you have in the account after 3 years?

• $2,100.00

• $2,382.03

• $2,000.00

• $2,500.00

A viral video is viewed by 1,000 people on the first day and the views double every day. How many views will it have on the 5th day?

• 16000

• 20000

• 8000

• 4000

A town's population is 20,000 and is growing at a rate of 3% per year. What will the population be in 10 years?

• 25000

• 26878

• 22000

• 30000

A certain type of investment grows by a factor of 1.1 each year. If you start with $500, how much will you have after 6 years?

• 885.78

• 600.00

• 750.50

• 950.00

A culture of yeast grows exponentially, starting with 250 cells. If it doubles every hour, how many cells will there be after 5 hours?

• 8000

• 5000

• 10000

• 4000