Understanding Exponents Through Stories

A bacteria culture doubles in size every hour. If it starts with 5 bacteria, how many will there be after 4 hours?

• 80

• 100

• 40

• 20

A tree grows 3 times its height every year. If it is initially 2 meters tall, what will its height be after 3 years?

• 18 meters

• 54 meters

• 24 meters

• 6 meters

A certain investment triples every 5 years. If you invest $100, how much will it be worth after 15 years?

• 900

• 3600

• 1500

• 2700

A computer's processing speed doubles every 2 years. If it starts at 1 GHz, what will its speed be after 6 years?

• 4 GHz

• 8 GHz

• 16 GHz

• 2 GHz

A population of rabbits increases by a factor of 4 every year. If there are 10 rabbits now, how many will there be in 2 years?

• 160

• 80

• 200

• 40

A certain type of crystal grows 5 times larger every month. If it starts at 2 cm, what will its size be after 3 months?

• 10 cm

• 100 cm

• 50 cm

• 250 cm

A car's value depreciates to half its value every 4 years. If it is worth $20,000 now, what will it be worth after 12 years?

• $5,000

• $2,500

• $10,000

• $15,000

A savings account earns interest that doubles the amount every 10 years. If you start with $500, how much will you have after 30 years?

• $2000

• $1000

• $4000

• $3000

A certain species of fish quadruples its population every year. If there are currently 15 fish, how many will there be in 4 years?

• 3840

• 240

• 960

• 600

A light bulb's brightness decreases to one-third every year. If it starts at 1200 lumens, what will its brightness be after 3 years?

• 800 lumens

• 600 lumens

• 400 lumens

• 44.44 lumens