>> Basic Statistics
A psychologist has developed a test to measure self-control. The test is normed so that it has a mean of 100 and a standard deviation of 15... The scores are normally distributed in the population of college students used to develop the test.
a. What is the percentile rank of a score of 80?
b. What percentage of scores falls between 80 and 120?
c. What is the standard score for a test score of 90?
d. What proportion of students should score above 120?
e. What is the cutoff point below which 87% of all scores fall?