Lithium Batteries The stability of measurementson a

QUESTION:

Lithium Batteries The stability of measurementson a manufactured product is important in maintaining productquality. A manufacturer of lithium batteries, such as theones used for digital cameras, suspected that one of the productionlines was producing batteries with a wide variationin length of life. To test this theory, he randomly selected n 50 batteries from the suspect line and n 50 from a linethat was judged to be in control. He then measured thelength of time (in hours) until depletion to 0.85V with a5-Ohm load for both samples. The sample means and variancesfor the two samples were as follows:Suspect Line Line in Controlx1 9.40 x2 9.25s1 .25 s2 .12a. Do the data provide sufficient evidence to indicatethat batteries produced by the suspect line have alarger variance in length of life than those producedby the line that is assumed to be in control? Testusing a .05.b. Find the approximate p-value for the test and interpretits value.c. Construct a 90% confidence interval for the varianceratio.