Standard Deviation can be used to determine how precise a series of calculations are in relation to one another.

Mean Evaluation 

Example #1: Understanding Standard Deviation

Example #2: Data below gives the volumes obtained by a chemist from the use of a pipet. Determine the standard deviation.

24.9 mL, 25.0 mL, 24.8 mL, 24.6 mL, 24.6 mL, 24.3 mL