In a psychology class of 100 students, test scores are normally distributed with a mean of 80 and a standard deviation of 5 . Approximately what percentage of students have scores between 70 and 90?
a. 68
b. 80
c. 95
d. 99
Question 2
Karen's first psychology exam score is 1 standard deviation from the mean in a normal distribution. The test has a mean of 75 and a standard deviation of 5 . Karen's percentile rank would be:
a. 16.
b. 54.
c. 70.
d. cannot say from the information given