#include <iostream>
#include <string>
#include <vector>

using namespace std;

int main(){
    vector<int> v;
    int n; double sum=0; cin >> n;
    for(int i=0; i<n; ++i){
        int a; cin >> a;
        sum += a;
    }
    cout << sum/(double)n << endl;
    return 0;
}