#include <bits/stdc++.h>
int main() {
  int i, n;
  float ans = 0.0;
  scanf("%d", &n);
  float arr[n];
  for (i = 0; i < n; i++) scanf("%f", &arr[i]);
  for (i = 0; i < n; i++) ans = ans + (float)(arr[i]) / 100;
  printf("%.12f", (float)((ans * 100) / n));
}
