#include <bits/stdc++.h>
using namespace std;
inline int read() {
  int s = 0;
  char c;
  while ((c = getchar()) < '0' || c > '9')
    ;
  do {
    s = s * 10 + c - '0';
  } while ((c = getchar()) >= '0' && c <= '9');
  return s;
}
bool descending(int a, int b) { return a > b; }
string toStr(char c) { return string(1, c); }
const int maxN = (int)1e2 + 10;
const int inf = (int)1e9;
int x;
int a[maxN];
long long dp[maxN];
vector<int> vl;
int main() {
  int n;
  cin >> n;
  int cnt = 0;
  for (int i = 0; i < (n); i++) {
    cin >> x;
    cnt += x;
  }
  cout << fixed << setprecision(12);
  cout << cnt / double(n) << endl;
}
