Question

1. Airport managment has made some improvement in its baggage claim system. the variance of waitibf time at the baggage claim is believed to be 16.0 minutes. after the improvement were made, a random sample of 14 passengers was selected to determine the variance of waiting time. the list below contains the sample data.

14 24 21 19 16 28 23

22 29 17 15 12 18 20

1). give a 95% confidence interval of the variance of waiting time at the baggage claim

2). Give a 95% confidence interval of the standard deviation of waiting time at the baggage claim.

2. the fan blades on commercial jet engines must be replaced when wear on these parts indicates too much variability to pass inspection. if a single fan blade broke during operation, it could severely endanger a flight. a large engine contains thousands of fan blades, and safety regulations require that variability measurements on the population of all blades not exceed s^2=0.18mm^2. An engine inspector took a random sample of 71 fan blades from an engine. she measured each blade and found a sample variance of 0.31 mm^2. Using a 0.01 ;even of significance, is the inspector justified in claiming that all the engine fan blades must be replaced.

Answer 1

As per Chegg guidelines we should solve only the first question with its sub parts. So I have done it. Please post the other questions differently mentioning your requirements