Growth and Decay Problems

Lauren has $90 in a savings account. The interest rate is 5%, compounded annually. To the nearest cent, how much will she have in 2 years?

• $99.23

• $21.98

• $56.46

• $9.21

A cliff overlooking Oak Grove Lake is experiencing erosion, losing elevation at a rate of 5% every millennium. The cliff's current elevation is 1,200 meters. What will its elevation be in 6 millennia? (Round to the nearest whole number if necessary).

• 882

• 465

• 349

• 975

Kelsey deposited $30 in a savings account earning 10% interest, compounded annually. To the nearest cent, how much interest will she earn in 3 years?

• $9.93

• $2.01

• $17.60

• $5.75

Thanks to its environmental initiatives, Silvergrove has cut its annual CO2 emissions by 5%. This year, the town produced 290,000 metric tons of emissions. If the downward trend continues, how much CO2 will be produced 7 years from now? (Round to the nearest whole number if necessary).

• 202,518

• 135,792

• 78,376

• 20,658

The mice population is 25,000 and is decreasing by 20% each year. What will be the mice population after 3 years?

• 12,800

• 15,777

• 102, 475

• 2,500

Your new computer cost $1500 but it depreciates in value by about 18% each year. How much will your computer be worth in 6 years? (Round to the nearest cent.)

• $456.01

• $556.98

• $778.22

• $332.63

Does the following equation represent growth or decay?

• Growth

• Decay

A town has a population of 8,000 people, and it grows at a rate of 3% per year. Which equation represents the population after t years?

A city's population is 12,000 and it decreases by 2% annually. Which equation represents the population after t years?

A population of 5,000 grows by 4% each year. What is the population after 5 years?

• 5849 people

• 5000 people

• 6083 people

• 4077 people