An important feature of tales is vattery life, the number of hours before the battery needs to be recharged. The file Tablets contains the battery life of 12 WiFi-only and 7 3G/4G/WiFi 9 through 12-inch tablets.
a. Assuming that the population variances from both types of tablets are equal, is there evidence of a difference in the mean battery life between the two types of tables? (Use a=0.05)
b. Determine the p-value in (a) and interpret its meaning.
c. Assuming that the population variances from both types of tablets are equal, construct and interpret a 95% confidence interval estimate of the difference between the population mean battery life of the two types of tablets.