#include <bits/stdc++.h>
int main() {
  int n, a[100], sum = 0;
  long double ans;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", a + i);
    sum += a[i];
  }
  ans = (long double)sum * 100 / (n * 100);
  printf("%Lf", ans);
  return 0;
}
