#include <bits/stdc++.h>
using namespace std;
double a[1001];
int main() {
  double c, d;
  int n, i;
  cin >> n;
  d = 0;
  for (i = 0; i < n; i++) {
    cin >> a[i];
    d = d + a[i];
  }
  c = d / (100.0 * n);
  c = c * 100;
  cout << fixed << setprecision(12) << c << endl;
  return 0;
}
