Question: A factory produces rubber hoses for the automotive industry. The factory has two inspectors (Joe and Sam) who measure the final products to make sure that they are the correct length. The factory manager wants to determine if there is a significant difference in the measurements made by these two individuals. He has each of them measure the same set of 15 hoses.

Use this information to answer questions 5 - 7.
5. Select all of the correct null and alternative hypotheses.
Choose at least one answer.
A. H0: = 0
B. H0: μ ≠ 0
C. HA: μ ≠ 15
D. HA: μ > 0
E. H0: μ = 0
F. H0: μ = 15
G. HA: μ ≠ 0
H. HA: μ < 15
6.The resulting measurements (in cm) have been saved in StatCrunch. Use the data to compute the test statistic and p-value for the difference between Joe and Sam.

The resulting test statistic is
The corresponding p-value is
7.From this hypothesis test, choose the correct conclusions.

Select all that apply.
Choose at least one answer.
A. We conclude that there is not a significant difference between the two employees' measurements.
B. We reject the null hypothesis.
C. Sam has larger values then Joe.
D. We fail to reject the null hypothesis.
E. We conclude that there is a significant difference between the two employees' measurements.
F. We can not tell whether Joe or Sam has larger values.
G. Joe has larger values then Sam.  Edit

Answer: 5. Null hypothesis: A. H0: = 0
Alternative hypothesis: B. H0: μ ≠ 0

6. z=0 (because, mean difference=0)
p=0

hence z=0<1.96(at alpha = 0.05)
Null hypothesis is accepted.

7. A. We conclude that there is not a significant difference between the two employees' measurements.
D. We fail to reject the null hypothesis.
  Edit