Does 3+ mean 3 and up or more than 3? this is a stupid question, but i don't remember lol

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?

Which of the following is the explicit rule for a geometric sequence defined a recursive formula of a -5a for which the first term is 23?

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83