A standardized test has a mean score of 500 points with a standard deviation of 100 points. Five studentsʹ scores are shown below.
Adam: 575 Beth: 690 Carlos: 750 Doug: 280 Ella: 440
Which of the students have scores within two standard deviations of the mean?
A)Adam, Beth, Carlos, Ella
B)Carlos, Doug
C)Adam, Beth, Ella
D)Adam, Beth

Question

Quizplus · Accepted Answer

Scores within two standard deviations of the mean (500) range from 300 (500 - 2*100) to 700 (500 + 2*100). Adam (575), Beth (690), and Ella (440) fall within this range.

A Standardized Test Has a Mean Score of 500 Points