You are analyzing the sample of waiting times in Exercise 23. The population standard deviation of the waiting times should be less than 2.5 minutes. Does the confidence interval you constructed for s suggest that the variation in the waiting times is at an acceptable level? Explain your reasoning.

Data from Exercise 23:

You are analyzing the sample of bolts in Exercise 13. The population standard deviation of the bolts’ diameters should be less than 0.5 inch. Does the confidence interval you constructed for σ suggest that the variation in the bolts’ diameters is at an acceptable level? Explain your reasoning.

Data from Exercise 13:

The diameters (in inches) of 18 randomly selected bolts produced by a machine are listed. Use a 95% level of confidence.

Transcribed Image Text:

4.477 4.425 4.034 4.317 4.003 3.760 3.818 3.749 4.240 3.941 4.131 4.545 3.958 3.741 3.859 3.816 4.448 4.206