Question

An important feature of tablets is battery life, the number of hours before the battery needs to be recharged. The following table shows the battery life of 12 WiFi-only and 7 3G/4G/WiFi 9-through 12-inch tablets:

WiFi Only	3G/4G+WiFi
12.40	11.70
10.60	11.40
11.50	10.70
12.60	11.50
8.00	11.30
10.90	11.60
11.60	8.90
10.00
10.90
8.90
9.50
10.50

1. Assuming that the population variances from both types of tablets are equal, is there evidence of a difference in the means battery life between the two types of tablets?

(Use α= 0.05).

2. Determine the p-value and interpret its meaning.

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.

Answer 1