Hypothesis Test 1- Mean - Sigma Known - on the TI-83-84 Plus and TI-Inspire w/84 keyboard

Using the Program ZTEST in group CH08Vn

The group CH08Vn must be in RAM see: Changing Groups

Example 1)

a) Identify the null and alternative hypothesis and label the claim,

b) critical value and test statistic,

c) P-value,

d) conclusion about the null hypothesis, and

e) final conclusion that addresses the original claim.

The health of employees is monitored by periodically weighing them in. A sample of 54 employees has a mean weight of 183.9 lb. Assuming that σ is known to be 121.2 lb, use a 0.10 significance level to test the claim that the population mean of all such employees weights is less than 200 lb.

Solution: First, set up the null and alternate hypothesis

a) Identify the null and alternative hypothesis and label the claim (Setup Info)

Run the program and fill in the answers:  PRGM Þ ZTEST Þ ENTER Þ ENTER (see Notes above and "More Solutions" below)

>choose 6 to run or another if you want to make changes     Output>      <End of Output  >choose 9 to quit or another if you want to make changes     End of Output   press 9

More Solution:

b) critical value -1.2816 test statistic-.9762

c) P-value .1645 Note: When the p-value gets tiny (smaller than any possible alpha) the programs uses <.001

d) conclusion about the null hypothesis Fail-to Reject Ho

e) final conclusion (Must use flowchart)  .  (Use the short version.) There is not sufficient evidence to support the claim that the U < 200 pounds.

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