Real-World Word Problems: Growth & Decay Challenges

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

• 2000

• 4000

• 3000

• 1000

A car's value decreases by 15% each year. If the car is worth $20,000 now, what will its value be after 2 years?

• $14,450

• $12,000

• $16,000

• $18,000

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

• 8 feet

• 12.16 feet

• 10 feet

• 15 feet

A savings account earns 4% interest compounded annually. If you deposit $1,000, how much will you have in the account after 5 years?

• 1216.65

• 1500.00

• 1100.00

• 1000.00

A radioactive substance decays at a rate of 10% per hour. If you start with 200 grams, how much will remain after 3 hours?

• 100 grams

• 220 grams

• 180 grams

• 145.8 grams

A population of rabbits increases by 25% each month. If there are 80 rabbits now, how many will there be in 3 months?

• 100

• 200

• 156

• 120

A certain species of fish decreases in population by 20% each year. If there are currently 1,000 fish, how many will be left after 2 years?

• 640

• 720

• 800

• 500

A bank offers a 6% annual interest rate compounded monthly. If you invest $500, how much will you have after 3 years?

• 598.34

• 450.00

• 575.25

• 620.50

A certain type of mold grows exponentially. If it starts with 10 spores and doubles every day, how many spores will there be after 5 days?

• 500

• 640

• 150

• 320

A tree's height decreases by 3% each year due to disease. If it is currently 15 feet tall, what will its height be after 2 years?

• 13.5 feet

• 14.12 feet

• 15.5 feet

• 12.75 feet