Question

A set of data is normally distributed with a mean of 52 and a standard deviation of 5. What percentage of the data is in the interval 47-57?

Answer 1

68. The 68-95-99.7 percent rule states that 68% falls within one standard deviation, 95% within 2, and 99.7% within 3. Since the standard deviation is 5, 47 and 57 are both one away, and because of that rule, the answer you need is 68%. Hope this helps.