Calculating the standard deviation of a set of data
Note: Enter numbers separated by spaces
Calculating the mean of a set of grouped data
Note: Enter the grouped data (one group per line in the format
"lower bound(lb) - upper bound(ub): frequency(f)"). Space should
be between "lb" and "-"" likewise "ub" and "-", and between ":"
and "f"
E.g: 10 - 19: 6