#include <bits/stdc++.h>
using namespace std;
int a;
double b[999999], c = 0;

int main() {
	cin >> a;
	for (int i = 1; i <= a; i++) {
		cin >> b[i];
		c += b[i];
	}
	cout << c / a * 1.0;
	return 0;
}