Question

In Colorado, the average ACT score is 20.1 with a standard deviation of 1.3. We collect a random sample of 35 students who took the exam last year.

Part 1: (6 pts)

Check the all necessary conditions in detail (not just yes or no) (1 pt each) and give the sampling model and parameters to 2 decimal places (2 pts).

Part 2: (8 pts)

What is the probability that the average composite ACT score is 19.5 or less? Show your calculations for finding the z-score to three decimal places (4 pts), then find the probability to four decimal places using the appropriate probability notation (2 pts). Write a sentence that gives your solution in context (2 pts).

Answer 1