Ch15 Linear Transformations and Combinations Classwork 1. A study of how well freshmen adapt the first six weeks of the school year was done. 50 randomly selected 9 th graders office referral records were examined to determine how often the ninth graders needed administrative guidance to a positive road to follow on campus. # of referrals, x 0 1 2 3 4 5 6 P(X = x) .46 .22 .12 .10 .06 .02 .02 a. What is the expected number of referrals? b. What is the variance and standard deviation of number of referrals? If we add 7 to the list of x above and then multiply it by -2 then: c. What is the new mean number of referrals? d. What is the new variance and standard deviation? 2. Suppose the equation Y = 200 + 10X converts a PSAT math score, X, into an SAT math score, Y. Suppose the average PSAT math score is 48 with a standard deviation of 1.5.
- Summer '16