THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Let the random variable X follow a normal distribution with a mean of 61.7 and a standard deviation of 5.2.
-What proportion of the total area under the normal curve is within ± two standard deviations of the mean?
A)About 50%
B)About 68%
C)About 95%
D)About 99.7%

Question

Quizplus · Accepted Answer

In a normal distribution, about 95% of the total area is within ± two standard deviations of the mean. This is known as the 95% empirical rule or the 68-95-99.7 rule. Therefore, the correct answer is option C.