Which of the following is the mean of the test scores listed below? 90, 87, 74, 84, 93, 78
A. 87
B. 78
C. 90
D. 84
The mean of a data set is the total scores divided by the number of tests.
Total test scores =90+87+74+ 84+93+76=504
Number of tests =6 Mean test score =506/6=84
The mean test score is 84
Therefore, the Correct Answer is D.