For these exercises, perform each of these steps. Assume that all variables are normally or approximately normally distributed.
a. State the hypotheses and identify the claim.
b. Find the critical value(s).
c. Compute the test value.
d. Make the decision.
e. Summarize the results.
Use the traditional method of hypothesis testing unless otherwise specified and assume the variances are unequal.

Find the 95% confidence interval for the difference of the means in Exercise 6 of this section.

Data from in Exercise 6

Upright vacuum cleaners have either a hard body type or a soft body type. Shown are the weights in pounds of a random sample of each type. At α = 0.05, can it be concluded that the means of the weights are different?

Transcribed Image Text:

21 16 23 13 18 Hard body types 17 17 20 17 15 20 16 17 17 16 18 15 Soft body types 11 24 13 12 15 13