Growth and Decay

Identify the following exponential as a growth or decay function.

 $y\ =\ 45\left(1.48\right)^x$  

• Growth

• Decay

Identify the following exponential as a growth or decay function.

 $y\ =\ 3\left(0.75\right)^x$  

• Growth

• Decay

• Growth of 93%

• Decay of 93%

• Growth of 7%

• Decay of 7%

• Growth of 14%

• Decay of 14%

• Growth of 86%

• Decay of 86%

A town has a population of 20000 and grows at 4% every year. What will be the population after 6 years, to the nearest whole number?

• 23397

• 25200

• 28370

• 25306

An element with mass 290 grams decays by 13.2% per minute. How much of the element is remaining after 10 minutes, to the nearest 10th of a gram?

• 101.9

• 70.4

• 61.1

• 78.1

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

• y = 15(35)^x
• y = 15(1.35)^x
• y = 15(0.35)^x
• y = 35(1.15)^x

Suppose a culture of bacteria begins with 5000 cells and decays by 30% each year.

Write an equation that represents this situation.

• y=5000(0.70)^x

• y=30(5000)^x
• y=5000(1.30)^x

• y=5000(.30)^x

In the function f(x)=1.25(0.65)^x , is this growth or decay and by how much?

• Growth by 25%

• Growth by 65%

• Decay by 25%

• Decay by 35%

The population of a certain town is modeled by f(x)=6191(1.04)^x . By what percent did the population increase by each year?