Mobile Device Repair Costs researcha) In a random sample of 12 mobile devices,
Mobile Device Repair Costs researcha) In a random sample of 12 mobile devices, the mean
repair cost was $90.42 and the standard deviation was $33.61.
b) You research repair costs of mobile devices and find that the population mean is $89.56. In a), does the t-value fall between -t95 and t0.95?