#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int arr[n];
  int total = 0;
  for (int i = 0; i < n; i++) {
    scanf("%d", &arr[i]);
    total += arr[i];
  }
  double ans;
  ans = (double)total * 100 / (double)(n * 100);
  printf("%.11f", ans);
}
