Answer Key on Describing Data
Instructions: For each of the data sets listed below, calculate the mode, median, mean, and range.
a. 1, 5, 5, 4, 4, 1, 1, 2
Mode 1
Median 3
Mean 2.8
Range 4
b. 20, 30, 40, 50, 70, 70
Mode 70
Median 45
Mean 46.6
Range 50
c. 100, 110, 100, 105, 110
Mode 100,110
Median 105
Mean 105
Range 10
d. 1, 3, 4, 2, 5, 6, 7
Mode na
Median 4
Mean 4
Range 6
Instructions: Answer the following question by calculating z-scores.
You scored a 1250 on you SATs and a 24 on your ACTs. Based on the information provided below, on which of these two college entrance exams did you do better?
Average score on SATs = 1200
Standard deviation on SATs = 100z = (1250-1200)/100 = 0.5
Average score on ACTs = 23
Standard deviation on ACTs= 0.5z = (24-23)/0.5 = 2
Did better on the ACT
You got a 80 on your first Comm. Theory exam and a 65 on the second exam. Given the information provided below. On which exam did you do better?
Average score on first exam 60
Standard deviation on first exam 10z = (80-60)/10 = 2
Average score on second exam 55
Standard deviation on second exam 5z = (65-55)/5 = 2
Did the same on Both Exams