using System;

public class Program

{

    public static void Main()

    {

        int num=0;

        double avg=0.00;

        int sum=0;

        int counter=0;

        for (int i=4;i<=8;i+=4)

             {

                 for (int j=0;j<=9;j++)

                 {

                     num =i*10;

                     num=num+j;

                     num=num*10;

                     num=num+(i/2);

                     counter++;

                     sum=sum+num;

                 }

             }

             avg=sum/counter;

            Console.WriteLine(avg);

    }

}