Growth or Decay Word Problems

Classify the model as Exponential GROWTH or DECAY.
A=10(1.01)³

• Growth

• Decay

Daniel’s Print Shop purchased a new printer for $35,000. Each year it depreciates at a rate of 5%. How much will the printer be worth in 8 years?

• $23,219.72

• $136.72

• $51,710.94

• $16,710.94

A population of a city is 422,000 and increases by 12% each year. Use an exponential function to find the population of the city after 8 years.

• 100,144 people

• 1,083,024 people

• 1,044,856 people

• 200,000 people

Twenty years ago, Mr. Davis purchased his home for $160,000. Since then, the value of the home has increased about 5% per year. How much is the home worth today?

• $176,783.29

• $424,527.63

• $57,357.75

• $532,041,076.80

Your shiny new boat cost $7650.  The depreciation for your boat is 14% per year. Estimate the value of your vehicle in 3 years. What is the equation that models this problem?

• y= 7650(.14)³

• y= 7650(.86)³

• y= 7650(1+.86/1)^3*1

Someone drops a basketball from a height of 10 feet. Each time it bounces, the bounce height decreases by 1/3. Which statement is correct?

• The decay rate is 1/3

  and the decay factor is 2/3

• The decay rate is 2/3

  and the decay factor is 1/3

If 10 mg of iodine 131 is given to a patient, how much is left after 24 days? The half-life of iodine-131 is 8 days.

• 25mg

• 1.25g

• 10g

• 10mg

The value of a car is $15,000 and depreciates at a rate of 8% per year. What is the exponential equation?

• y=8(15,000)^x

• y=15,000(1.08)^x

• y=15,000(0.92)^x

• y=15,000(0.08)^x

You have inherited land that was purchased for $30,000 in 1990. The value of the land increased by approximately 5% per year. What is the approximate value of the land in the year 2011?

• $83,579

• $10,217

• $14,963,655

• $28,500

Is this exponential growth or decay?

• Growth because a=1

• Decay because b=0.5

• Growth because there is no a

• Neither because a=0