If a particular set of data is approximately normally distributed, we would find that approximately
A) 2 of every 3 observations would fall between ±1 standard deviation around the mean.
B) 4 of every 5 observations would fall between ±1.28 standard deviations around the mean.
C) 19 of every 20 observations would fall between ±2 standard deviations around the mean.
D) all the above

Question

Quizplus · Accepted Answer

The empirical rule, also known as the 68-95-99.7 rule, states that for a normal distribution, approximately 68% of the data falls within one standard deviation of the mean, 95% falls within two standard deviations of the mean, and 99.7% falls within three standard deviations of the mean.

If a Particular Set of Data Is Approximately Normally Distributed