Out of students that take course A, the average final grade…

Out of students that take course A, the average final grade (mean) for the course is 71.4 with a standard deviation of 7.5. a.  What is the z-score for someone that had a 89 in course A? [a]  (round to the nearest hundredth…0.01) b.  What percent of students average less than 89? [b] c.  If 412 students enroll in course A, how many students would you expect to have an average that is less than 89? [c]

A given population has a mean of 268 with a standard deviati…

A given population has a mean of 268 with a standard deviation of 17.  A sample of 64 items is selected from this population.   [a] What is the standard deviation for the sampling distribution of sample means? Round to 2 decimal places [b] What is the mean of the sampling distribution? [c] What is the probability that a random sample of size 64 has a mean that is less than 272?