The computed value of 95% confidence interval for the average lifetime of a certain type of passenger car baterries, based on random sample of 100 batteries, is (LCL-3.2 years, UCL=6.8 vears). From the computed confidence interval the sample mean, xbar, and the samle standard deviation; must have been equal to: xbar-5 and 5-9.184 We can not compute xbar and since we do not have the orginal data xbar-10 and 5-0.9184 xbar-10 and 5-9.184'
