Growth and Decay: Graphing Exponential Changes in 10th Grade

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

• 2000

• 4000

• 10000

• 8000

A radioactive substance has a half-life of 5 years. If you start with 80 grams, how much will remain after 15 years?

• 5 grams

• 10 grams

• 20 grams

• 40 grams

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?

• $10,000

• $5,000

• $7,680

• $12,000

A certain species of fish in a lake triples in population every year. If there are currently 200 fish, how many will there be after 4 years?

• 400

• 16200

• 6400

• 800

A certain medication in the bloodstream decreases by 25% every hour. If the initial amount is 200 mg, how much will remain after 4 hours?

• 100 mg

• 63.28125 mg

• 50 mg

• 150 mg

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

• 6.5 feet

• 8.05 feet

• 7.25 feet

• 10 feet

A certain type of investment grows at an annual rate of 8%. If you invest $1,000, how much will it be worth after 10 years?

• 1500.00

• 1800.50

• 2158.92

• 2000.00

A certain type of bacteria dies off at a rate of 30% per hour. If you start with 1,000 bacteria, how many will remain after 2 hours?

• 600

• 800

• 490

• 700

A population of rabbits increases by 50% every month. If there are currently 40 rabbits, how many will there be after 6 months?

• 300

• 458

• 120

• 200

A certain chemical decays at a rate of 15% per day. If you start with 200 grams, how much will remain after 10 days?

• 20 grams

• 100 grams

• 50 grams

• 39.37 grams