#include <bits/stdc++.h> 
using namespace std;

int main()
{
	int n;
	cin >> n;
	int a[n+5];
	double sum;
	for(int i = 1; i <= n; i++)
	{
		cin >> a[i];
		sum+=a[i];
	}
	sum/=n;
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	
	printf("%.2f", sum);
	
	
	
	
	
	
	
	return 0;
}