Question

The commercial for the new Meat Man Barbecue claims that it takes 20 minutes for assembly. A consumer advocate thinks that the assembly time is lower than 20 minutes. The advocate surveyed 14 randomly selected people who purchased the Meat Man Barbecue and found that their average time was 17.4 minutes. The standard deviation for this survey group was 3.6 minutes. What can be concluded at the the αα = 0.01 level of significance level of significance?

1. For this study, we should use Select an answer z-test for a population proportion t-test for a population mean
2. The null and alternative hypotheses would be:

H0:H0:  ? p μ  ? > = < ≠       

H1:H1:  ? p μ  ? < ≠ = >    

3. The test statistic ? z t  =  (please show your answer to 3 decimal places.)
4. The p-value =  (Please show your answer to 4 decimal places.)
5. The p-value is ? > ≤  αα
6. Based on this, we should Select an answer reject accept fail to reject  the null hypothesis.
7. Thus, the final conclusion is that ...
   • The data suggest the population mean is not significantly lower than 20 at αα = 0.01, so there is statistically insignificant evidence to conclude that the population mean amount of time to assemble the Meat Man barbecue is equal to 20.
   • The data suggest the populaton mean is significantly lower than 20 at αα = 0.01, so there is statistically significant evidence to conclude that the population mean amount of time to assemble the Meat Man barbecue is lower than 20.
   • The data suggest that the population mean amount of time to assemble the Meat Man barbecue is not significantly lower than 20 at αα = 0.01, so there is statistically insignificant evidence to conclude that the population mean amount of time to assemble the Meat Man barbecue is lower than 20.

Answer 1

(g)

The data suggest the populaton mean is significantly lower than 20 at α = 0.01, so there is statistically significant evidence to conclude that the population mean amount of time to assemble the Meat Man barbecue is lower than 20.