The following data represent the battery life, in hours, for a
random sample of 10 full charges on a fifth-generation iPod music
player.
7.3
10.2
12.9
10.8
12.1
6.6
10.2
9.0
8.5
7.1
What is the average battery life of this random sample of 10
full charges?
Construct a 95% confidence interval for the mean number of
hours the battery will last on this player.
What is the margin of error for the battery life of the 10 full
charges?
What condition did you have to assume for your
calculations?
Suppose you wanted more accuracy to estimate the mean number of
hours the battery will last on this player. How many more trials of
full charges should be added to the sample above to be 95% sure
that the sample mean is within half an hour of the population mean
battery life?