We don’t like to find broken crackers when we open the package. How can makers reduce breaking? One idea is to microwave the crackers for 30 seconds right after baking them. Randomly assign 65 newly baked crackers to the microwave and another 65 to a control group that is not microwaved. After 1 day, none of the microwave group were broken and 16 of the control group were broken. Let p₁= the true proportions of crackers like these that would break if baked in the microwave and p₂ = the true proportions of crackers like these that would break if not microwaved.

Check if the conditions for calculating a confidence interval for p₁ − p₂ are met.