#include<algorithm>

#include<cmath>

#include<cstdio>

#include<iostream>

using namespace std;

int main(){

int n;

double f,sum=0;

cin>>n;?

for(int i=1;i<=n;i++){

cin>>f;

sum+=f;

}

printf("%.4lf",sum/n);

return 0;

}