1. Two hundred raffle tickets are sold. Your friend has five people in her family who each bought two raffle tickets. What is the probability that someone in her family will win the raffle?
2. Jolie has 45 minutes to do her statistics homework. If the mean is 38 minutes and the standard deviation is 3 calculate Jolie’s z score. Once calculated, interpret your findings in terms of Jolie’s performance. (Hint: use the normal distribution and the probability that the other students performed better or worse.)
3. A psychologist measures units of change for a memory test after students are given an opportunity to sleep only four hours. The following change units were obtained: 7,-12,4, -7, 3, -10. Find the
d) standard deviation