Exploring Exponential Decay and Compound Interest: Grade 10 Quiz

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?

• $12,282.50

• $8,500

• $10,000

• $15,000

A population of bacteria doubles every 4 hours. If you start with 500 bacteria, how many will there be after 12 hours?

• 8000

• 4000

• 1000

• 2000

You invest $1,000 in a savings account that offers an annual interest rate of 5%, compounded annually. How much money will you have after 3 years?

• 1100.50

• 1200.00

• 1157.63

• 1050.75

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

• 5 grams

• 10 grams

• 20 grams

• 40 grams

A certain type of plant grows at a rate of 10% per month. If you start with 200 plants, how many will you have after 6 months?

• 400

• 354

• 300

• 250

You deposit $2,500 in a bank account that pays 3% interest compounded quarterly. How much will you have in the account after 5 years?

• $3,000.00

• $2,500.00

• $2,750.00

• $2,904.00

A car depreciates in value according to the formula V(t) = V0 * e^(-kt), where V0 is the initial value, k is the decay constant, and t is time in years. If a car's initial value is $25,000 and k is 0.1, what will its value be after 5 years?

• 20000

• 15163.75

• 18000

• 12500

A certain medication's effectiveness decreases by 20% every hour. If the initial effectiveness is 100%, what will be the effectiveness after 3 hours?

• 60%

• 75%

• 40%

• 51.2%

You invest $5,000 in a fund that earns 6% interest compounded monthly. How much will you have after 4 years?

• 6106.93

• 5000.00

• 7000.00

• 5500.50

A tree's height increases by 15% each year. If the tree is currently 10 feet tall, how tall will it be after 2 years?

• 15 feet

• 13.225 feet

• 14.5 feet

• 12 feet