Aperson play a game of chance has 0.25 probability of winning. if the person plays the game 20 times and wins half of that number of times what is the difference between the theoretical probability and experimental probability of that person winning

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard 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?