For a variable that is normally distributed with a mean of 100 and a standard deviation of 25, approximately ______ of the scores are between ______ and ______.
A) 68%; 75 and 125
B) 68%; 50 and 150
C) 95%; 100 and 150
D) 95%; 100 and 200

Question

Quizplus · Accepted Answer

The 68-95-99.7 rule for a normal distribution states that approximately 68% of the data falls within one standard deviation of the mean. Given a mean of 100 and a standard deviation of 25, one standard deviation above and below the mean would be 75 (100-25) and 125 (100+25), respectively.

For a Variable That Is Normally Distributed with a Mean