Overall, the students' class attendance days (per year academic) is normally distributed around 180 days with a standard deviation of 15 days.

What's the probability that the mean number of attendance days will be between 190 and 200?
Students that are in the top 5% will receive a 20% off coupon at the "Crazy" cafeteria. What is the minimum number of attendance days that you should have in order to receive such discount?
The students at or below the 20%ile of number of attendance days must attend a counseling session with one of the advisers. At least how many attendance days you should have in order to not have to attend such session?
How likely (what is the probability) is it to have the number of days attended above 175?
How likely (what is the probability) is it that Cri (name not previously mentioned) will have her attendance days between 165 and 205 days?
What percentile does an attendance of 220 attendance days rank at?
What percentile does an attendance of 180 attendance days rank at?
If 9 students (9 = size of the sample) selected randomly attended the school, what's the likelihood that their mean number of attended days will be within 10 days of the population mean? (mean +/- 10).