Critical values for quick reference during this activity.

confidence level / critical value

0.90.....z*=1.645

0.95.....z*=1.960

0.99.....z*=2.576

The manager of a bookstore with a coffee shop wants to know the proportion of customers that come into the store because of the coffee shop. A random sample of 75 customers was polled. Use Sheet 1 of the Excel file linked above to calculate p^ and the 95% confidence interval.

p^=?

Upper bound for 95% confidence interval = ?

Lower bound for 95% confidence interval = ?

The manager can say with 95% confidence that the true population proportion of the customers that come into the store because of the coffee shop is in the interval [ , ]?