The average lactation (nursing) period of all earless seals is 24 days, Grey seals are one of several types of earless seals. A sample of 44 female grey seals had the following lactation periods, in days:

20.9	28	21.8	23.9	23.2
24.2	20.4	23.7	20.1	24.4
21.2	25.3	19.9	23.6	18.5
23.9	16.6	21.8	20.6	24.1
21	21.8	21.5	20.5	24.3
26	25	24.2	24.1	21.3
16.9	24.8	19.9	22.8	17.4
18.2	21.5	21.2	17.9	23
19.7	21.7	25.5	26.4

At the 5% significance level, do the data provide sufficient evidence to conclude that average lactation (nursing) period of grey seals is different from 24 days? Assume that the population standard deviation is 2.7 days. (Note: The average and the standard deviation of the data are respectively 22.11 days and 2.66 days.)

Procedure: Select an answer One mean T Hypothesis Test One variance χ² Hypothesis Test One proportion Z Hypothesis Test One mean Z Hypothesis Test

Assumptions: (select everything that applies)

Step 1. Hypotheses Set-Up:

$\displaystyle {H}_{{0}}:$  Select an answer p σ² μ =	, where Select an answer σ² p μ is the Select an answer population mean population proportion population variance and the units are Select an answer days months years weeks
$\displaystyle {H}_{{a}}:$ Select an answer μ p σ² ? ≠ > <	, and the test is Select an answer Right-Tailed Two-Tailed Left-Tailed

Step 2. The significance level $\displaystyle \alpha=$ %

Step 3. Compute the value of the test statistic: Select an answer z χ² t = (Round the answer to 3 decimal places)

Step 4. Testing Procedure: (Round the answers to 3 decimal places)

CVA	PVA
Provide the critical value(s) for the Rejection Region:	Compute the P-value of the test statistic:
left CV is and right CV is	P-value is

Step 5. Decision:

CVA	PVA
Is the test statistic in the rejection region?	Is the P-value less than the significance level?
? no yes	? yes no

Conclusion: Select an answer Do not reject the null hypothesis in favor of the alternative. Reject the null hypothesis in favor of the alternative.

Step 6. Interpretation:

At 5% significance level we Select an answer DO NOT DO have sufficient evidence to reject the null hypothesis in favor of the alternative hypothesis.