#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cctype>
#include<cstring>
#include<string>
#include<vector>
#include<set>
#include<stack>
#include<queue>
#include<iostream>
#include<iomanip>
#include<ctime>
#include<algorithm>
#include<map>
// const int MAXN=1e5;
// double sz[MAXN];
using namespace std;

int main(){
    int a;
    double ans;
    scanf("%d",&a);
    for(int i=1;i<=a;i++){
        double in;
        scanf("%lf",&in);
        ans+=in;
    }
    double out=ans/a;
    printf("%.4f",out);
}