C++ :

#include <iostream>
#include <climits>
using namespace std;
int main() {
	int n;
  cin >> n;
  double sum = 0;
  for (int i = 0; i < n; ++i) {
    double x;
  	cin >> x;
    sum += x;
  }
  printf("%.4lf", sum / n);
  return 0;
}