A Major Airline Company Is Concerned That Its Proportion of Late

Short Answer

A major airline company is concerned that its proportion of late arrivals has substantially increased in the past month. Historical data shows that on average 18 percent of the company airplanes have arrived late. In a random sample of 1,240 airplanes, 310 airplanes have arrived late. If we are conducting a hypothesis test using the critical value rule to determine if the proportion of late arrivals has increased, what is the value of the calculated test statistic?