#include<iostream>
using namespace std;
int main()
{
	int n,x;
	double sum=0;
	cin>>n;
	x=n;
	for(int i=1;i<=x;i++)
	{
		cin>>n;
		sum+=n;
	}
	sum=sum/x;
	cout<<sum<<endl;
	return 0;
}