I need to calculate the avg

using System;
using System.Linq;

class Program
{
    static void Main()
    {
    //
    // Use Average to compute average value.
    //
    double[] array1 = { 1, 2, 3, 5, 0 };
    double average1 = array1.Average();
    Console.WriteLine(average1);
    //
    // Use Average to compute average string length.
    //
    string[] array2 = { "dog", "cat", "perls" };
    double average2 = array2.Average(x => x.Length);
    Console.WriteLine(average2);
    }
}