using System;

namespace _05.AverageNumber
{
    class AverageNumber
    {
        static void Main(string[] args)
        {
            int number = int.Parse(Console.ReadLine());
            int sum = 0;

            for (int i = 0; i < number; i++)
            {
                int currentNumber = int.Parse(Console.ReadLine());
                sum += currentNumber;
            }

            double average = sum * 1.0 / number;
            Console.WriteLine($"{average:f2}");

        }
    }
}