Concept explainers
For Exercises 7 through 20, assume that all variables are
a. State the hypotheses and identify the claim.
b. Find the critical value.
c. Compute the test value.
d. Make the decision.
e. Summarize the results, and explain where the differences in the means are.
Use the traditional method of hypothesis testing unless otherwise specified.
18. Calories hi Fast-Food Sandwiches Three popular fast-food restaurant franchises specializing in burgers were surveyed to find out the number of calories in their frequently ordered sandwiches. At the 0.05 level of significance, can it be concluded that a difference in
FF#1 | FF#2 | FF#3 |
970 | 1010 | 740 |
880 | 970 | 540 |
840 | 920 | 510 |
710 | 850 820 |
510 |
Source: www.fatcalories.com

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