Question 1 - You happen to know that the average GPA (grade point average) for the 5,000 sophomores at USC is 2.8 with a population standard deviation of .25. Amazingly, the GPAs are normally distributed. If you take a random sample of 40 sophomores, what is the probability that the average gpa will be more than 2.9?
a) .0057
b) .7257
c) .9943
d) .2743
Question 2 - You happen to know that the average GPA for the 5,000 sophomores at USC is 2.8 with a population standard deviation of .25. Amazingly, the GPAs are normally distributed. If you take a randomly chosen sophomore, what is the probability that her gpa will be less than 2.9?
a) .0057
b) .3446
c) .9943
d) .6554
Question 3 - A lumber manufacturer sells framing lumber. The length of their boards are normally distributed and average 8 ft long with a standard deviation of .04 ft. What are the odds that if you took a sample of 50 boards that their average would be less than 8.015 ft?
a) .0040
b) 2.66
c) .6462
d) .9960
Question 4 - You happen to know that the average GPA (grade point average) for the 5,000 sophomores at USC is 2.8 with a population standard deviation of .25. If you take a sample of 30 sophomores, there is a ten percent chance the sample average will be less than what value?
a) 2.48
b) 2.742
c) 1.282
d) 2.858