A major car dealership has several stores in a big city. The owner wants to determine if there is a difference in the proportion of SUVs that are sold at stores A and B. The owner gathers the sales records for each store from
the
past year. A random sample of 55 receipts from store A shows that 30 of the sales were for SUVs. Another random
sample of 60 receipts from store B shows that 42 of the sales were for SUVs. Assuming conditions for inference
are met, what is the 99% confidence interval for the difference in proportions of sales that are SUVs?
Find the Z-table here.