TABLE 6-1
The manager of a surveying company believes that the average number of phone surveys completed per hour by her employees has a normal distribution. She takes a sample of 15 days output from her employees and determines the average number of surveys per hour on these days. The ordered array for this data is: 10.0, 10.1, 10.3, 10.5, 10.7, 11.2, 11.4, 11.5, 11.7,
11.8, 11.8, 12.0, 12.2, 12.2, 12.5.
-Referring to Table 6-1, the data appear reasonably normal but not perfectly normal.

Question

Quizplus · Accepted Answer

According to Table 6-1, if the mean and median are close together and the range is not too large compared to the sample size, the data can be considered reasonably normal. In this case, the ordered array shows a gradual increase in values and the mean (11.6) is similar to the median (11.7), indicating normality. However, there are a few outliers at the lower and higher ends of the range, suggesting some deviation from perfect normality.

TABLE 6-1 The Manager of a Surveying Company Believes That the Average