#include <iostream.h>
#include <fstream.h>
#include <iomanip.h>

void main()
{ 
        ifstream infile("numbers.txt");

        int number = 0, amount = 0;
		long total;
		double avg;

		while (infile >> number) {
			total += number;
			amount++;
		}
		
		avg = double(total) / double(amount);
		cout << setiosflags (ios::fixed);        
		cout << setprecision(2);
		cout << avg;
		cout << "\n\n";
}