Assume a normal distribution of data. What percent of the population will fall between 1 and 2 standard deviations above the mean?

Answer 1

According to the empirical rule, 95% of the population with be within ±2 standard deviations. There is 68% that fall within ±2 standard deviation. If you are just looking for above the mean between these values, and not both, divide these percentages in half.

68/2 = 34%

95/2 = 47.5%

The difference between them is 47.5 - 34 = 13.5%