#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    double x=0;
    for(int i=1;i<=n;i++){double a;cin>>a;x+=a;}
    printf("%.2f",x/n);
    return 0;
}

#include<iostream>
#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
int main(){
	int n;
	double d;
	cin >> n;
	int age;
	int res = 0;
	for(int i=1;i<=n;i++){
		cin >> age;
		res+=age; 	
	} 
	d = 1.0*res/n;
	printf("%.2lf",d);
	return 0;
}