Problem 1576. Mean and standard deviation of times in string

Input(t) - cell of strings with times in format 'min:sec.ms'

Output([m, s]) - two strings with mean and standard deviation with the same format (rounded to first decimal place)

Example:

• t={'45.5', '1:04.8', '55.4'}; m='55.2'; s='9.7';
• t={'1:38.4', '2:12.9', '2:00.6'}; m='1:57.3'; s='17.5'