2 people are trying different phones to see which one has the better talk time. ChatLong has an average of 18 hours with a stand
ard deviation of 2 hours and Talk-a-Lot has an average of 20 hours with a standard deviation of 3. The two people who tested their phones both got 20 hours of use on their phones. For the z-scores I got 1 for the ChatLong company and 0 for Talk-a-lot. What is the percentile for each z-score?
The percentile for the z scores are gotten from the normal distribution table. The z cores are already known.
1) For the ChatLong company, the z score is 0. The area corresponding to the z score from the normal distribution table is 0.5. Therefore, the percentile is
0.5 × 100 = 50%
2) For the Talk-a-lot company, the z score is 1. The area corresponding to the z score from the normal distribution table is 0.84. Therefore, the percentile is