Question: Your Detroit division produced 135 defective parts out of the total production of 983 last week. The Kansas City division produced 104 defectives out of 1,085 produced during the same time period.
a. Find the percent defective for each division and compare them.
b. Find the difference between these two percentages (Detroit minus Kansas City) and interpret it.
c. Find the standard error for this difference using the large-sample formula.
d. Find the 95% confidence interval for the difference.
e. Test to see if these two divisions differ significantly in terms of quality of production, based on the defect rate.