AvarageNumber

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        double sum = 0;
        for (double i = 0; i < n; i++) {

            Scanner scanner = new Scanner(System.in);
                double num = scanner.nextDouble();
                sum=sum+num;

        }
        double result = sum/n;

        System.out.printf("%.2f", result);
    }
}