Wks 06 ____________, ____________: _______ Surname (e.g. “Straayer”), Given Name (e.g. “Dave”) Class time 1. A population of values has a normal distribution with μ=100 and σ=15. You intend to draw a random sample of size n=33. What is the mean of the distribution of sample means? ____________________________ What is the standard deviation of sample means? ____________________________ Why or why not can we assume that shape of the distribution of sample means to be approximately normal? Reason 1: _______________________________________________________ ________________________________________________________ Reason 2: ________________________________________________________ _________________________________________________________ 2. Given data in problem 1, what is the probability that a single randomly-selected member of the population is more than 120? P(X>120) = _______________________________ 3. Given data in problem 1, what is the probability that the average of a random sample of size 33 is greater than 120? P(X-bar>120) = _______________________________ 4. Find the 90th percentile (P90). This is the value that separates the bottom 90% from the top 10% of values. 5. Given samples of size 33, find the 90th percentile (P90) of the means.