Constructing a Confidence Interval about a Population Proportion Using StatCrunch
Step 3 Go to www.statcrunch.com. Select Stat > Proportions > One Sample > with Summary. Fill in
the window as shown:
Click Next> Choose the Confidence Interval radio button. Enter the appropriate level of confidence.
Select Standard-Wald from the drop down men.
Click Calculate.
L. Limit represents the lower bound on the confidence interval and U. Limit represents the upper bound
on the confidence interval. So,
Lower bound: 0.307
Upper bound: 0.373