#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, p[100], total = 0;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &p[i]);
    total += p[i];
  }
  double perc = ((float)total / (n * 100)) * 100;
  printf("%.6f", perc);
  return 0;
}
