using System;
using System.Linq;
using System.Collections.Generic;
 
public class Test
{
	public static void Main()
	{
        var list = new List<string>() { "50:James", "23:Jessica", "70:Ricky", "70:Dodger", "50:Eric" };
		var ordered = list.Select(s => new { Str = s, Split = s.Split(':') })
            .OrderByDescending(x => int.Parse(x.Split[0]))
            .ThenBy(x => x.Split[1])
            .Select(x => x.Str)
            .ToList();
        foreach(string s in ordered)
            Console.WriteLine(s);
	}
}

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