Percent Growth and Decay

Determine if the following is an example of a linear OR exponential situation:

A certificate of deposit earns 4% interest each year.

• Linear

• Exponential

• Neither

Kelli's mom takes a 400 mg dose of aspirin. Each hour, the amount of aspirin in a person's system decreases by about 29%. Write an equation to represent the amount of aspirin left in her system x hours after she took the aspirin.

• growth:

  0.2% increase

• growth:

  2% increase

• decay:

  98% decrease

• decay:

  2% decrease

The value of an early American coin increases in value at a rate of 6.5% annually. If the purchase price of the coin this year is $1,950, write an equation to model the value in x years.

• growth:

  10% increase

• growth:

  90% increase

• decay:

  90% decrease

• decay:

  10% decrease

You need $200 to start a snow cone stand for the summer. You borrow the money from a bank that charges 4% interest compounded monthly. Choose the expression that represents the amount owed after 3 years.

The value of a house increases in value by 1.5% each year.

• Linear

• Exponential

• Neither

Malik bought a new car for $15,000. He was told that the car's value will decrease by 15% every year. Write an equation to represent the car's value after x years.

The original value of a painting is $1400, and the value increases by 9% each year. Write an exponential growth function to model this situation.

• y=1400(1.09)^x

• y=1.09(1400)^x

• y=1400(.91)^x

• y=1.09^x

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x

• y = 15(1 + 0.35)^x

• y = 15(0.35)^x

• y = 35(1+ 0.15)^x