Author Question: Assume that your class took an exam last week and the mean and standard deviation of the exam were ... (Read 78 times)

serike · **on:** Jun 20, 2018

Assume that your class took an exam last week and the mean and standard deviation of the exam were 85 and 5, respectively. Your instructor told you that 30 percent of the students had a score of 90 or above. You would probably

a. think that your instructor was out of her mind.
b. decide that your score of 80 would probably fall in the failing range.
c. conclude that the scores were not normally distributed.
d. conclude that such a set of scores could not possibly happen.

Question 2

If we have data that have been sampled from a population that is normally distributed with a mean of 50 and a standard deviation of 10, we would expect that 95 of our observations would lie in the interval that is approximately

a. 3070.
b. 3550.
c. 4555.
d. 7090.