In a normal distribution, what percentage of scores will fall between one standard deviation below the mean and one standard deviation above the mean?

68%

To find the percentage of scores that fall between one standard deviation below the mean and one standard deviation above the mean in a normal distribution, you can use the empirical rule, also known as the 68-95-99.7 rule.

According to this rule, in a normal distribution:
- Approximately 68% of scores fall within one standard deviation of the mean.
- Approximately 95% of scores fall within two standard deviations of the mean.
- Approximately 99.7% of scores fall within three standard deviations of the mean.

Since we are interested in the range between one standard deviation below the mean and one standard deviation above the mean, we can apply the principle that 68% of scores fall within one standard deviation of the mean.

Therefore, the percentage of scores that will fall between one standard deviation below the mean and one standard deviation above the mean is approximately 68%.