## STATISTICS 310 At a manufacturing plant, the work-in-process

Question
At a manufacturing plant, the work-in-process (WIP) represents the number of days(measured in hundredths) from when the parts are completed and the assembled product is packaged for shipping. The company has the business objective of determining whether there are differences in the WIP between plants. Data from samples of 20 different products at each of two production plants are available below. Completely analyze the data.

What are the hypotheses to test to determine whether there are differences in the WIP between plants?

A. Ho: µa = µb B. Ho: ?a = ?b

H1: µa ? µb H1: ?a ? ?b

C. Ho: µd = 0 D. Ho pa = pb

H1: µd ? 0 H1: pa ? pb

Do the samples provide evidence that the populations are not approximately normally distributed?

A. The data suggest that the WIP values for plant A are skewed left.

B. The data suggest that the WIP values for plant B are skewed left.

C. The data suggest that the WIP values for both populations are skewed left.

D. The data suggest that the WIP values for both plants are approximately normal.

Do the samples provide evidence that the population variances are not equal at the 0.05 level of significance?

The test statistic for the F test for the ratio of two variances, Fstat, is ______. The p-value for Fstat is _____, soassume/do not assume the population variances are equal.

What test will determine whether there are differences in the WIP between plants?

A. The paired t test for the means of two related populations

B. The chi-squared test for the standard deviation

C. Two-way ANOVA

D. The pooled-variance t test for the difference between two means

E. The chi-squared test for the difference between two proportions

F. One-way ANOVA

G. The t test for the difference between two means, assuming unequal variances

Are there differences in the WIP between plants at the 0.05 level of significance?

Since the p-value for the test statistic, X2stat/Zstat/tstat = _______ is, conclude that there are/ are no differences in the WIP between plants.

A
11.71
12.42
20.16
4.49
10.18
9.72
5.18
11.96
6.29
12.31
7.61
16.33
8.98
15.54
8.24
13.74
7.55
6.05
8.59
5.19

B
8.18
16.03
12.15
14.99
12.07
11.05
16.24
8.34
5.41
8.44
6.49
3.62
6.92
6.98
14.43
13.72
16.13
15.29
10.58
25.83