#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  double frac[n];
  for (int i = 0; i < n; i++) cin >> frac[i];
  double sum = 0;
  for (int i = 0; i < n; i++) {
    sum += (frac[i] / 100);
  }
  cout << (sum / n) * 100 << fixed << endl;
  return 0;
}
