SOLUTION: Please help me solve this: A certain brand of alcohol claims that the alcohol concentration of the product is 70%. To test this claim, a random sample of 15 bottles of this br

Algebra ->  Statistics  -> Hypothesis-testing -> SOLUTION: Please help me solve this: A certain brand of alcohol claims that the alcohol concentration of the product is 70%. To test this claim, a random sample of 15 bottles of this br      Log On


   

Question 1174738: Please help me solve this:
A certain brand of alcohol claims that the alcohol concentration of
the product is 70%. To test this claim, a random sample of 15
bottles of this brand were tested and an average of 68% alcohol
concentration was obtained with a standard deviation of 8%. Is the
claim valid at the 0.05 level of significance?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi

Sample:  n = 15 , mean = .68,  sd = .08

Ho: u =  .70 (claim)
Ha: u < .70
------------------

 t(.68) = (.68 -.70)/[.08/sqrt(15)] = -.0645
 p-value = P( t< -.0645 when df = 14) = .47

Since the p-value is greater than 5%, fail to reject Ho.
Conclusion: The claim is reasonable at the 5% confidence level.

Wish You the Best in your Studies.