Growth and Decay D

1. Classify the model as Exponential Growth or Decay. A = 800(1.12)^x

• Growth
• Decay

2. Is this graph exponential growth or decay?

• growth
• decay

3. Pick the equation that is exponential decay

• y = 950(.38)^x
• y = 78(1.23)^x

4. Pick the equation that is exponential growth

• y = 2(5.1)^x
• y = 5(0.32)^x

5. What is the initial value, for the function: f(x) = 21000(.65)^x

6. Which of the following functions shows an initial amount of $300 and an increase of 20% each year?

• y=20(300)^x
• y = 300(1.2)^x
• y = 300(0.8)^x
• y= 300(0.2)^x

7. What is the decay rate in the following model? A= 200(.45)^6

• .45
• 200
• 6
• .55

8. Write an equation that models the situation. A population of 1200 beetles is too large to sustain and decreases in population each month at a rate of 15%. Write an equation to represent this situation.

9. Solve the equation you wrote in #9 to determine the the number of beetles after 10 years.

10. The number of mosquitoes at the beginning of the summer was 4000. The population of mosquitoes is expected to grow at a rate of 25% a month. Write an equation to represent this situation.