Exponential Growth & Decay

Rates

100

Is the following growth or decay: y = 2^x

What is growth

200

Is the following growth or decay: y=100(0.5)^x

What is decay

300

Identify the growth rate: y= 100(1+0.4)^x

40%

400

Identify the decay rate: y = 7(0.94)^x

6%

500

Identify the percent change: y = 350(0.75)^x

25%

Given Equation

100

For the equation y = 5(1.5)^t What is the initial value?

What is 5

200

The equation y = 250(1.2)^t represents the number of people entering a stadium. How many people were initially in the stadium?

250

300

The equation y = 250(1.2)^t represents the number of people entering a stadium, where t represents minutes. How many people were in the stadium after 5 minutes? Round to nearest whole number.

622

400

The equation y = 250(1.2)^t represents the number of people entering a stadium. What is the rate at which the number of people are increasing?

20%

500

The equation y = 45(0.2)^t represents the number of rabbits in a park. Find the rate at which the rabbit population is changing. Identify if its growth or decay.

80% decay

Write Equation

100

Write an exponential growth function to model the situation. A population of 422,000 increases by 12% each year.

What is y= 422,000(1+.12)^x

200

The population of Baconburg starts off at 20,000, and grows by 13% each year. Write an exponential growth model and find the population after 10 years.

What is y = 20,000(1+.13)^10 and population of 67,891

300

The Hippityhoppity bunny decided to have a family reunion at the Magic Forest every 5 years. During the second reunion the family discovered that the number of family members was 154 and was growing at an annual rate of 3.2%. Write an equation to model the growth of the bunny family.

What is y = 154(1+.032)^x

400

The fish in The Magic Forest Lake were declining at an annual rate at 1.5%. Their current number is estimated at 2500. Write an equation to model the decreasing number of fish.

What is y = 2500(.985)^x

500

The fish in The Magic Forest Lake were declining at an annual rate at 6%. Their current number is estimated at 2500. Write an equation and use it to predict the number of fish in the lake in 10 years, rounded to the whole number.

 y = 2500(.94)^x and 1347