#include<bits/stdc++.h>
using namespace std;
//const int N = 1000010;
//int a[N];
int main()
{
    int n;
    float res,ans;
    cin >> n;
    for (int i = 1;i <= n;i++)
    {
        int x;
        cin >> x;
        res += x;
    }
    ans = res / n;
    printf("%.4f",ans);
    return 0;
}