#include<iostream>
using namespace std;
int main()
{
    int n,x;
    scanf("%d",&n);
    double sum=0;
    x=n;
    for(int i=1;i<=x;i++)
    {
        scanf("%d",&n)
        sum+=n;
    }
    sum/=x;
    printf("%lf",sum);
    return 0;
}