Wearout of used display panels. Researchers presented a study of the wearout failure time of used colored display panels purchased by an outlet store (Mathematical Sciences Colloquium, December 2001). Prior to acquisition, the panels had been used for about one-third of their expected lifetimes. The failure times (in years) for a sample of 50 used panels are reproduced in the next table, followed by an SPSS printout of the analysis of the data.
(a) Locate a 95% confidence interval for the true mean failure time of used colored display panels on the printout.
(b) Give a practical interpretation of the interval, part a.
(c) In repeated sampling of the population of used colored display panels, where a 95% con- fidence interval for the mean failure time is computed for each sample, what proportion of all the confidence intervals generated will capture the true mean failure time?
