#include <bits/stdc++.h>
using namespace std;
int n;
double p[105];
int main() {
  scanf("%d", &n);
  double k;
  double sum = 0;
  k = 100 * n;
  for (int i = 0; i < n; i++) {
    cin >> p[i];
    sum += p[i];
  }
  printf("%.12lf", (sum / k) * 100);
}
