Question

3. In a survey of 1,012 randomly selected U.S. adults, 47% said that they were satisfied with the quality of education students receive in kindergarten through grade twelve. You wish to test if the proportion of U.S. adults who are satisfied with the education that students receive in kindergarten through grade twelve is more than 50%.

[2 points] Give the null and alternate hypotheses.

[5 points] Using the formula and showing work, find the standardized test statistic.        

[10 points]

(a) By HAND, showing work, find a 95% confidence interval for the population mean if a sample of size 30 has mean 11.5 and standard deviation 4.5. Use t* = 2.05..

(b) Test the claim of a repair shop that people travel more than 3500 miles between oil changes. A random sample of 8 cars getting an oil change has a mean distance of 3375 miles since having an oil change with a standard deviation of 225 miles. By HAND showing work,

Answer 1

Conclusion:- hence we Reject null hypothesis (H0) at and fail to Reject null hypothesis (H0) at .