ALGEBRA 1 | UNIT #11 | 11.6.4 PRACTICE: MODELING : LINEAR, QUADRATIC, & EXPONENTIAL FUNCTIONS

National Park Animal Populations

You are studying the populations of three animals in a national park. Below are the data sets for the animal populations. Circle the park that you chose:

Yellowstone

x Year

y1 Population 1, Grizzly Bears

(per square mile)

y2 Population 2, Pocket Gophers

(per square mile)

y3 Population 3, Osprey

(per square mile)

x y1 y2 y3

0 4.0 4.0 4.0

1 4.5 4.5 5.8

2 5.0 5.3 7.2

3 5.5 6.4 8.2

4 6.0 8.1 8.8

5 6.5 10.6 9.0

8 8.0 28.6 7.2

10 9.0 60.7 4.0

Everglades

x Year

y1 Population 1, American Alligator

(per square mile)

y2 Population 2, Marsh Rabbit

(per square mile)

y3 Population 3, Florida Panther

(per square mile)

x y1 y2 y3

0 6.0 6.0 6.0

1 6.5 6.5 7.8

2 7.0 7.3 9.0

3 7.5 8.4 9.8

4 8.0 10.1 10.0

5 8.5 12.6 9.8

8 10.0 30.6 6.0

10 11.0 62.7 1.0

Make Sense of the Problem

What do you want to find out?

Analyze the Data

Population 1 (y1): (Write the animal species' name.)

Answer the following questions about the growth function of population 1:

1. Is population 1 increasing or decreasing? (0.5 point)

2. What is the rate of change between year 0 and year 1 for population 1? What is it between year 5 and year 10? Include calculations in your answer. (2 points)

3. Predict the average rate of change from year 5 to year 6 for population 1. Use the average rate of change you found in question 2 in your prediction. (1 point)

4. What type of function best models the growth for population 1? Give a reason for your answer. (1 point)

Population 2 (y2): (Write the animal species' name.)

Answer the following questions about the growth function of population 2:

5. What is the maximum population per square mile during the first 10 years for population 2? (0.5 point)

6. What is the average rate of change for population 2 between years 5 and 10 (x = 5 to x = 10)? (1 point)

7. The average rate of change for population 2 changes by a common ratio (multiplication) of 1.5 each year. What type of function best models this growth? (1 point)

8. Estimate the average rate of change from year 5 to year 6 for population 2. Remember, the average rate of change for this population changes by a ratio of 1.5 each year. Show your work. HINT: First find the average rate of change from year 4 to year 5. (3 points)

Population 3 (y3): (Write the animal species' name.)

Answer the following questions about the growth function of population 3:

9. What is the maximum population per square mile during the first 10 years for population 3? In what year did this occur? (1 point)

10. What is the average rate of change for population 3 between years 5 and 10 (x = 5 to x = 10)? Show your work. Identify the change as an increase or a decrease. (2 points)

11. What type of function best models the growth for population 3? Give a reason for your answer. (1 point)

12. Use the graph provided. When do all three populations contain the same number of animals? (1 point)

13. Use the following graphs to verify your work on this question.

A. Estimate the average rate of change from year 5 to year 8 for population 3. Show your work. (2 points)

B. Estimate the average rate of change from year 8 to year 10 for population 3. Show your work. (2 points)

C. Based on the answers to Parts A and B, estimate the number of animals in population 3 in year 15, and give a reason for your estimate. (1 point)

Here is my work.

Step-by-step explanation:

I got 85% on the assignment. Just FYI

I chose YELLOWSTONE.

What do you want to find out?

The population of the animals at yellowstone national park over the years.

1. Is population 1 increasing or decreasing?

Population 1 is increasing.

2. What is the rate of change between year 0 and year 1 for population 1? What is it between year 5 and year 10? Include calculations in your answer.

rate of change for year 0-1 = .5 ROC for year 5-10, 2.5.

3. Predict the average rate of change from year 5 to year 6 for population 1. Use the average rate of change you found in question 2 in your prediction.

The average rate of change is 1.25.

4. What type of function best models the growth for population 1? Give a reason for your answer.

This is a linear function. each year the population is increasing by the same amount. ( .5) this makes the function linear.

Population 2. (Pocket gopher.)

5. What is the maximum population per square mile during first 10 years for population 2?

The maximum population for the first 10 years is 60.7.

6. What is the average rate of change for population 2 between years 5 to 10 (x=5 to x=10)?

10.02.

7. The average rate of change for population 2 changes by a common ratio (multiplication) of 1.5 each year. What function best models this growth?

An exponential function best models this growth.

8. Estimate the average rate of change from year 5 to 6...

ROC=4.0

9. What is the maximum population per square mile during...

9.0. this occurred in year 5.

10. what is the average rate of change..

The average rate of change is -1. the population is decreasing.

11. What type of function best models the growth..

Quadrilateral.

12.

YEAR 0. ALL POPULATIONS WERE 4

13.

ANSWER: AVERAGE RATE OF CHANGE (ROC) -0.6

B:

AVERAGE ROC= -1.6

C

BECAUSE THE POPULATION IS DECREASING AT 1 PER YEAR, ON YEAR 15 THE POPULATION WILL BE LESS THAN 0.

I DID YELLOWSTONE

I GOT A 100

Step-by-step explanation:

Make sense of the problem:

what is the estimated population for each animal at year 12.

Population 1 grizzly bear

1.  Is population 1 increasing or decreasing? (0.5 point)

Increasing

2. What is the rate of change between year 0 and year 1 for population 1? What is it between year 5 and year 10? Include calculations in your answer. (2 points)

The rate of change between year 0 and year 1 is .5 and the rate of change between year 5 and 10 is also .5

3. Predict the average rate of change from year 5 to year 6 for population 1. Use the average rate of change you found in question 2 in your prediction. (1 point)

I think the average rate of change from year 5 to year 6 is .5 this is because each year the population is increasing by .5 according to question 2.

4. What type of function best models the growth for population 1? Give a reason for your answer. (1 point)

A linear function would model population 1 the best. This is because the population is increasing by .5 each year. It increases as a steady rate so it will be a straight line.

Population 2 pocket gophers

5. What is the maximum population per square mile during the first 10 years for population 2? (0.5 point)

The maximum population per square mile during the first 10 years is 60.7.

6. What is the average rate of change for population 2 between years 5 and 10 (x = 5 to x = 10)? (1 point)

The average rate of change is 10.02

7. The average rate of change for population 2 changes by a common ratio (multiplication) of 1.5 each year. What type of function best models this growth? (1 point)

A exponential function would best model this growth.

8. Estimate the average rate of change from year 5 to year 6 for population 2. Remember, the average rate of change for this population changes by a ratio of 1.5 each year. Show your work. HINT: First find the average rate of change from year 4 to year 5. (3 points)

The rate of change from year 5 to year 6 is about 3.75 since population 2 changes by a ratio of 1.5 each year. The rate of change from year 4 to 5 is 2.5 so 2.5*1.5 is 3.75.

Population 3 Osprey

9. What is the maximum population per square mile during the first 10 years for population 3? In what year did this occur? (1 point)

The maximum population per square mile during the first 10 years is 9.0 this occured in year 5.

10. What is the average rate of change for population 3 between years 5 and 10 (x = 5 to x = 10)? Show your work. Identify the change as an increase or a decrease. (2 points)

The change is a decrease.

11. What type of function best models the growth for population 3? Give a reason for your answer. (1 point)

A quadratic function best models the growth for population 3 because at first the population increases but then it decreases.

12. Use the graph provided. When do all three populations contain the same number of animals? (1 point)

In year 0 all three populations contained the same amount of animals.

13. Use the following graphs to verify your work on this question.

A. Estimate the average rate of change from year 5 to year 8 for population 3. Show your work. (2 points)

7.2-9/8-5 = -1.8/3 = -0.6

B. Estimate the average rate of change from year 8 to year 10 for population 3. Show your work. (2 points)

4-7.2/10-8 = -3.2/2 = -1.6

C. Based on the answers to Parts A and B, estimate the number of animals in population 3 in year 15, and give a reason for your estimate. (1 point)

The number of animals in year 15 will be 0 this is because the number of animals keeps steadily going down and you cannot have a negative number of animals.

step-by-step explanation:

20% of 120 is 24. if you subtract 24 from 120 you get 96