Answer:
a) Null hypothesis: 
Alternative hypothesis :
b) 
If we compare the p value and the significance level given 
we see that 
so we can conclude that we have enough evidence to reject the null hypothesis.
c) We can conclude that the mean is significantly less than 16 ounces at 10% of significance. so then the consumer suspect is correct.
Explanation:
Data given and notation
represent the mean for the sample
represent the sample standard deviation
sample size
represent the value that we want to test
represent the significance level for the hypothesis test.
t would represent the statistic (variable of interest)
represent the p value for the test (variable of interest)
State the null and alternative hypotheses.
Is a one tailed left test.
What are H0 and Ha for this study?
Null hypothesis:
Alternative hypothesis :
The degrees of freedom on this case are:
Compute the test statistic
The statistic for this case is given by:
(1)
t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".
Calculate the statistic
We can replace in formula (1) the info given like this:
Give the appropriate conclusion for the test
Since is a one side left tailed test the p value would be:
Conclusion
If we compare the p value and the significance level given we see that so we can conclude that we have enough evidence to reject the null hypothesis.
We can conclude that the mean is significantly less than 16 ounces at 10% of significance. so then the consumer suspect is correct.
