Exponential Growth & Decay: Real-World Applications

A population of bacteria doubles every 3 hours. If there are initially 500 bacteria, how many will there be after 12 hours?

• 2000

• 10000

• 8000

• 4000

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

• $8,500

• $10,000

• $15,000

• $12,282.50

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

• 1469.33

• 1000.00

• 1200.00

• 2000.00

The half-life of a radioactive substance is 10 years. If you start with 80 grams, how much will remain after 30 years?

• 40 grams

• 5 grams

• 20 grams

• 10 grams

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

• 11.75 feet

• 12.16 feet

• 13.0 feet

• 10.5 feet

A certain species of fish in a lake is known to increase its population by 25% each year. If there are currently 200 fish, how many will there be after 2 years?

• 312

• 400

• 300

• 250

A bank offers a savings account with a 6% interest rate compounded annually. If you deposit $500, how much will you have in the account after 4 years?

• 631.24

• 500.00

• 700.00

• 600.00

A certain type of mold grows exponentially. If a colony starts with 100 spores and triples in size every day, how many spores will there be after 5 days?

• 15000

• 30000

• 24300

• 8100

A car depreciates in value according to the equation V(t) = 20000(0.85)^t, where V is the value and t is the number of years. What will the value of the car be after 4 years?

• 10440.13

• 15000.75

• 9500.50

• 12000.00

A scientist is studying a culture of cells that grows according to the model N(t) = 200e^(0.3t), where N is the number of cells and t is time in hours. How many cells will there be after 5 hours?

• 1200

• 500

• 896

• 750