9.22 The mean arrival rate of flights at O'Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the 30 days of marginal weather the mean arrival rate is 200 flights per hour.

210	215	200	189	200	213	202	181	197	199
193	209	215	192	179	196	225	199	196	210
199	188	174	176	202	195	195	208	222	221

1. Set up a right-tailed decision rule at a = .025 to decide whether there has been a significant increase in the mean number of arrivals per hour.
2. Carry out the test and made the decision. Is it close? Would the decision be different if you use a= .01?
3. What assumptions are you making, if any?