Exam Scores
Exam scores. The average on a history exam (scored out of 100 points) was 85, with a standard deviation of 15. Is the distribution of the scores on this exam symmetric? If not, what shape would you expect this distribution to have? Explain your reasoning.
2.33 Stats scores. Below are the final exam scores of twenty introductory statistics students.
57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94
Create a box plot of the distribution of these scores. The five number summary provided below may be useful.
Min Q1 Q2 (Median) Q3 Max
57 72.5 78.5 82.5 94
Marathon winners. The histogram and box plots below show the distribution of finishing times for male and female winners of the New York Marathon between 1970 and 1999.
2.0 2.4 2.8 3.2 0
10
20
M ar
at ho
n tim
es 2.0
2.4
2.8
3.2
(a) What features of the distribution are apparent in the histogram and not the box plot? What features are apparent in the box plot but not in the histogram?
(b) What may be the reason for the bimodal distribution? Explain.
(c) Compare the distribution of marathon times for men and women based on the box plot shown below.
2.0 2.4 2.8 3.2
Women
Men
(d) The time series plot shown below is another way to look at these data. Describe what is visible in this plot but not in the others.
