A supermarket chain is testing a revised work flow. If the redesign is effective, then the process for all locations will be revised. For this decision, data has been collected in one location under the current design and one location under the new design. To make the new design standard, the difference in proportion of customer billing completed within 10 minutes should be 30% higher than it is right now.

A supermarket chain is testing a revised work flow. If the redesign is effective, then the process for all locations will be revised. For this decision, data has been collected in one location under the current design and one location under the new design. To make the new design standard, the difference in proportion of customer billing completed within 10 minutes should be 30% higher than it is right now.

Therefore, the null hypothesis here is that the two designs are more than 30% different from each other.