var times = new List<string>
{
"06:56",
"06:58",
"06:55",
"06:54",
"06:54",
"06:53",
"06:55",
"06:53",
"06:58",
"06:54",
"06:58",
"06:55",
"06:54",
"06:50",
"06:54",
"06:57"
};
var average = times
.Select(TimeSpan.Parse)
.Average(x => x.TotalMilliseconds);
var averageTime = TimeSpan.FromMilliseconds(average);
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