Question

A normal curve with a mean of 500 and a standard deviation of 100 is shown. Shade the region under the curve within one standard deviation of the mean. How much of the data falls within the shaded region?

Answer 1

The region between one standard deviation from the mean is (400,600) which should be 68.27% of the data.

Explanation:

The mean of this data set is 500 and the standard deviation is 100. The data that are within one standard deviation of the mean, must be in the range between 400 and 600, which according to the normal curve should be about 68.27% of the samples. The shaded region is shown in red on the attached figure.