Name______Period_____ Date______

Regression Using the Calculator

As a science project, Shelley is studying the relationship of car mileage (miles per gallon) and speed (miles per hour). The table shows the data Shelley gathered using her family’s hybrid vehicle.

Speed (miles per hour) 30 40 50 60 70

Mileage (miles per gallon) 34.0 33.5 31.5 29.0 27.5

SCATTERPLOT (sketch)

(label your axes!) 1. Graph the data as a scatter plot on your calculator. Make sure to use an appropriate window. Write the steps here:

2. Does the data appear to be LINEAR, QUADRATIC, or EXPONENTIAL?

3. Write your regression equation here (Round to the hundredths place): ______Write the steps here:

4. Paste your function into the y = menu and sketch the curve on your graph above. Write the steps here: 5. Use your model to predict the gas mileage for this car when you are going 45 miles per hour.

6. Use your model to predict how many miles per hour you could go and get 30 miles per gallon.

Using a ruler and measuring in cm, calculate the diameter and circumference of each circle.

Diameter Circumference

1. Record all of the data in your table. & enter the data into your calculator.

2. Graph the data as a scatterplot. Does the data appear to be LINEAR, QUADRATIC, or EXPONENTIAL?

3. Write your regression equation here: (Round to the hundredths place) ______

4. What does the y represent? 5. What does the x represent? 6. What is the slope of this line?

7. What does the slope represent in this problem? The table shows approximate run times for 16 mm films given the diameter of the film on the reel. Find an equation to model for the run time given the diameter.

1. What is our independent variable (x)? 2. What is our dependent variable (y)?

2. Graph the data as a scatter plot on your calculator. Does the data appear to be LINEAR, QUADRATIC, or EXPONENTIAL?

3. Write your regression equation here: (Round to the hundredths place) ______

4. Paste your function into the y = menu and sketch the curve on your graph above.

5. Use the model to estimate the run time for a roll of film with a diameter of 15 in.

The number of bacteria in a colony is growing at an exponential rate.

Time Bacteria

8 A.M. 100

9 A.M. 300

1. What is the a-value? (Use 8 A.M. as the start time.)

2. What is the percent of growth?

3. What is the b-value?.

4. What makes this function exponential versus linear

or quadratic?

5. Write an equation that models this situation. The table gives the amount of a 15-mg dose of antibiotic remaining in a person’s body after the given hours.

1. What is our independent variable (x)? 2. What is our dependent variable (y)?

3. Graph the data as a scatter plot on your calculator. Does the data appear to be LINEAR, QUADRATIC, or EXPONENTIAL?

4. Write your regression equation here: (Round to the hundredths place) ______

5. Paste your function into the y = menu and sketch the curve on your graph above.

6. What is the decay factor? 7. What percent of decay does this represent?

8. Use your table to predict the amount of antibiotic after 1 day.

9. Sketch the scatterplot with the regression function: