Which statement is true of normally distributed data?
Approximately 68% of data falls within 2 standard
deviations (±2) of the mean.
Approximately 68% of data falls within 1 standard
deviation (±1) of the mean.
Approximately 75% of data falls within 2 standard
deviations (±2) of the mean.
Approximately 75% of data falls within 1 standard
deviation (±1) of the mean.