sredno aritmetichno

using System;

public class Program
{
	public static void Main()
	{
		double[] ocenki = new double [6];
		ocenki[0]=5.50;
		ocenki[1]=3.40;
		ocenki[2]=6.00;
		ocenki[3]=4.50;
		ocenki[4]=5.30;
		ocenki[5]=3.60;

		double sum = 0;
		for (int i = 0;i<ocenki.Length; i++)
			sum += ocenki[i];
		{
		Console.WriteLine("Sum = {0:f2}", sum);

			double avg = sum / ocenki.Length;
			Console.WriteLine("Average = {0:f2}", avg);
		}
	}
}