A professor finds that the average SAT score among all stude…

A professor finds that the average SAT score among all students attending his college is 1,150 ± 150 (m ± s). He polls his class of 25 students and finds that the average SAT score is 1,200. Suppose he computes a one-sample z test at a .05 level of significance. What is his decision?

A researcher wants to know the probability of selecting a st…

A researcher wants to know the probability of selecting a student athlete from a school population where 5% of students are athletes. If the researcher selects a sample of 120 students, is it appropriate to use the normal approximation of the binomial distribution to estimate this probability?