#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i = (a); i < (b); ++i)
#define REP(i,n) FOR(i,0,n)
#define SZ(n) (int)(n).size()
#define ALL(n) (n).begin(), (n).end()
using namespace std;
typedef long long LL;
typedef vector<int> VI;

int main() {
	int n;
	cin >> n;
	VI a(n);
	REP(i, n) cin >> a[i];
	int sum = 0;
	REP(i, n) sum += a[i];
	cout << (double)sum / n << endl;
	return 0;
}