Liam is setting up folding chairs for a meeting. If he arranges the chairs in 8 rows of the same length, he has 11 chairs left over. If he arranges the chairs in 6 rows of that same length, he has 15 left over. How many chairs does Liam have?

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?