math 9 & 10
BUSA 2183 Introduction to Business Statistics
Summer 2019 –Session II
Short Exercise 10 (25 points)
IMPORTANT: In any question, if there is a calculation, first provide the formula and then show your calculations for your answers.
Please, provide your answers under each question.
Data files can be found in the D2L.
Question 1 (Short Exercise 2 in the book) (2*5=10 points)
A sample of 36 observations is selected from a normal population. The sample mean is 12, and the population standard deviation is 3. Conduct the following test of hypothesis using the .01 significance level.
Answer the questions:
(a) Is this a one- or two-tailed test?
(b) What is the decision rule?
(c) What is the value of the test statistic?
d) What is your decision regarding H0?
(e) What is the p-value? Interpret it.
Question 2 (Short Exercise 10 in the book) (2*3=6 points)
Given the following hypotheses:
A random sample of 12 observations is selected from a normal population. The sample mean was 407 and the sample standard deviation was 6. Using the .01 significance level:
a. State the decision rule.
b. Compute the value of the test statistic.
c. What is your decision regarding the null hypothesis?
Question 3 (Short Exercise 16 in the book) (2*3+3=9 points)
Given the following hypotheses:
A random sample of six resulted in the following values: 118, 105, 112, 119, 105, and 111. Assume a normal population. Using the .05 significance level, can we conclude the mean is different from 100?
a. State the decision rule.
b. Compute the value of the test statistic.
c. What is your decision regarding the null hypothesis?
d. Estimate the p-value. (3 points)