Mastering Exponential Growth and Decay in Real Life

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

• 2000

• 3000

• 4000

• 1000

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?

• $10,000

• $5,000

• $7,680

• $12,000

A bank offers an account that increases by 5% each year. If you deposit $1,000, how much will you have after 4 years?

• 1000.00

• 1215.51

• 1100.00

• 1500.00

A certain species of fish in a lake is known to decrease by 10% each year due to overfishing. If there are currently 1,200 fish, how many will be left after 2 years?

• 1,000

• 1,080

• 800

• 972

A tree grows 15% taller each year. If it is currently 4 meters tall, what will its height be after 2 years?

• 5.29 meters

• 6.2 meters

• 5.0 meters

• 4.6 meters

A town's population is 20,000 and is expected to grow by 3% each year. What will the population be after 5 years?

• 21000

• 23185

• 25000

• 20050

A radioactive substance decays by 25% every year. If you start with 80 grams, how much will remain after 2 years?

• 45 grams

• 30 grams

• 60 grams

• 50 grams

A savings account earns 6% interest compounded annually. If you start with $2,000, how much will you have after 3 years?

• 2400.75

• 2500.00

• 2382.03

• 2200.50

A certain type of plant grows by 12% each month. If you have 50 plants, how many will you have after 6 months?

• 75

• 98

• 120

• 60

A smartphone loses 15% of its value each year. If it was purchased for $800, what will its value be after 4 years?

• $417.61

• $500.00

• $350.25

• $680.00