For a thirty-day time period, studies indicate the average number of medical errors made by residents in hospitals is 17.4. The average is expected to be higher for residents with long work hours. To investigate this, a random of 25 residents with long work hours will be selected and medical errors closely monitored. An estimate from prior records indicates this group will average about 22.3 medical errors for a thirty-day period. Assume the distribution of medical errors is normal and the population standard deviation is known to be σ = 10.

If this study is to be carried out at the 0.05 significance level, the power of the study is .