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CSharp · Console

/Program.cs

using System.Linq;
using static System.Console;

public class Program
{
	public static void Main()
	{
		string teste = "#10##10##50##100#";
		
		var arr = teste.Split('#').ToList();
		arr.RemoveAll(x => x == "");
		
		decimal soma = 0;
		foreach(var v in arr)
		{
			decimal vlr;
			decimal.TryParse(v, out vlr);
			
			soma += vlr;
		}
		
		decimal media = soma / arr.Count;
		
		WriteLine($"Soma: {soma} Média: {media}");
	}
}