Author Question: Let x1 and x2 be 0 - 1 variables whose values indicate whether projects 1 and 2 are not done or are ... (Read 22 times)

sdfghj · **on:** Jun 24, 2018

Let x1 and x2 be 0 - 1 variables whose values indicate whether projects 1 and 2 are not done or are done. Which answer below indicates that project 2 can be done only if project 1 is done?
a. x1 + x2 = 1
b. x1 + x2 = 2
c. x1 - x2 0
d. x1 - x2 0

Question 2

It is crucial that the variance of a production process be less than or equal to 25 . A sample of 22 is taken. The sample variance equaled 26.
a. Construct a 90 confidence interval for the population variance.
b. Construct a 90 confidence interval for the population standard deviation.
c. State the null and alternative hypotheses to be tested.
d. Compute the test statistic.
e. The null hypothesis is to be tested at the 10 level of significance. State the decision rule for the test.
f. What do you conclude about the population variance?

jharrington11 · **Reply #1 on:** Jun 24, 2018

Answer to Question 1

D

Answer to Question 2

a. 16.7123 to 47.1043
b. 4.0881 to 6.8633
c. H0: 2 25
Ha: 2 > 25
d. 21.84
e. Reject H0 if 2 > 29.6151.
f. Do not reject H0, there is not sufficient evidence to conclude that the variance exceeds 25.