#include<bits/stdc++.h>
#define endl '\n'
#define MAXN 100000
using namespace std;

int main()
{
    int n, sum = 0, cnt = 0;
    cin >> n;
    while(n--)
    {
        int x;
        cin >> x;
        cnt++;
        sum += x;
    }

    cout << (double)sum / cnt << endl;

    return 0;
}