Answer: here is a lesson that helped me Discussion Points and Possible Answers
1. The table below shows the total fat in grams and total calories for various fast food items. Does this
data suggest that there is an association between the fat grams and total calories in fast food
items? Support your answer.
Sandwich Total fat (g) Total Calories
Hamburger 9 260
Cheeseburger 13 320
Quarter Pounder 21 420
Quarter Pounder with Cheese 30 530
Big Mac 31 560
Arch Sandwich Special 31 550
Arch Special with Bacon 34 590
Crispy Chicken 25 500
Fish Fillet 28 560
Grilled Chicken 20 440
Grilled Chicken Light 5 300
Sample Answers: The food items with more fat tend to have more calories, so it seems
reasonable that there is a positive association. Larger values of total fat tend to go with larger
values of total calories.
2. A scatter plot can be used to visualize the association between fat and calories. Think about how
the variables are related, and how the variables fat and calories should be placed on the
coordinate axes. Label the axes on the graph below, and explain your choice of axes and
variables.
Answer: Since the amount of fat in fast food affects the
total calories, the variable fat is the independent
variable. This variable is best to plot along the horizontal
axis. The variable calories is the dependent variable
and is, therefore, best to plot along the vertical axis.
Teacher Tip: Discuss with the students why fat is the independent variable
and calories is the dependent variable in this situation. Ask them whether
the amount of fat depends on how many calories are in the food, or the
amount of calories depend on how much fat is in the food.
Exploring Bivariate Data TEACHER NOTES
MATH NSPIRED
©2013 Texas Instruments Incorporated 3 education.ti.com
Move to page 1.2.
3. On page 1.2, fat grams are stored as a variable fat. Total
calories are stored as a variable cal. Construct a scatter plot for
these two variables:
a. Select the add variable text at the bottom of the page
where the horizontal axis should be placed, and select the
variable of your choice.
b. Select the add variable text on the left of the page where the vertical axis should be placed,
and select the variable of your choice.
Tech Tip: Variables fat and cal are stored in the document,
so students can select them to be plotted on the coordinate axes. Initially
the axes are not shown on the Data & Statistics page. When students
select the add variable text at the bottom of the screen, they will see the
choice of stored variables. After they select the independent variable, they
should select the add variable text on the left side of the screen to select
a dependent variable. The scatter plot with labeled coordinate axes will
Step-by-step explanation:
