WS 4.1
Name__________________________________Per________
For #1 – 4: The calories and total fat in grams listed in the chart below are based on a burger with bun, condiments
and cheese.
Burger
Calories
Total Fat (g)
McDonald’s Cheeseburger
300
12
McDonald’s Double Cheeseburger
440
23
Wendy’s 1/2 lb. Double with Cheese
700
40
Wendy’s 3/4 lb. Triple with Cheese
970
60
Burger King BK Double Stacker
620
39
Burger King BK Triple Stacker
820
55
Boca Cheeseburger
260
10
Carl Jr.’s Famous Star with Cheese
660
39
Carl Jr.’s Big Hamburger
460
17
1000
900
800
700
600
500
400
300
200
0
1.
10
20
30
40
50
60
Do you think calories explain fat or that fat explains calories?
Therefore, ………………… is the explanatory variable and ………………… is the response variable.
2.
Plot the ordered pairs on the grid above.
3.
Describe the relationship using a complete sentence.
4.
Are there any obvious outliers in the scatterplot? If so, name the point(s).
For #5 – 8: Match the correct correlation coefficient r with each scatterplot. All four scatterplots have been drawn
with the same scale and the same size window.
–0.98
5. r = …………
–0.89
–0.63
6.
0.15
r = …………
0.63
0.89
7. r = …………
0.98
8. r = …………
For #9 – 19: Below is a list comparing calories and total fat for only one burger from each of the five companies.
See #1.
Burger
Calories
Total Fat (g)
McDonald’s Cheeseburger
300
12
Wendy’s 1/2 lb. Double with Cheese
700
40
Burger King BK Double Stacker
620
39
Boca Cheeseburger
260
10
Carl Jr.’s Famous Star with Cheese
660
39
9. x = ……………
10. sx = ……………
11. y = ……………
12. sy = ……………
13. n = ………
14. Complete the following table using the values above.
x
xx
sx
y
yy
sy
 x  x  y  y 





 s x  s y 
Sum =
15. Use the formula for finding the correlation coefficient r, substituting in the values from the table above.
r
 x  x  y  y  1
1
    



n  1  s x  s y  
16. If we changed the fat content to milligrams in place of grams, what would happen to your answer for r?
17. If one additional slice of cheese were added to each burger, there would be an increase of 70 calories and an increase
of 5 grams of fat for each. What would happen to your answer for r?
18. What if the Boca Cheeseburger actually only had 160 calories. How would this effect r? Do you think that r would be
larger, smaller, or the same?
19. One student reported the value of r. labeling it as calories per gram of fat. Is this label correct? Why or why not?