A bootstrap distribution of mean commute times (in minutes) based on a sample of 500 St. Louis workers stored in CommuteStLouis is shown in Figure 5.13. The pattern in this dotplot is reasonably bell-shaped so we use a normal curve to model this distribution of bootstrap means. The mean for this distribution is 21.97 minutes and the standard deviation is 0.65 minutes. Based on this normal distribution, what proportion of bootstrap means should be in each of the following regions?

Figure 5.13

(a) More than 23 minutes
(b) Less than 20 minutes
(c) Between 21.5 and 22.5 minutes

Transcribed Image Text:

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