#include <stdio.h>
float avgt(int c,int t[])
{
    if (c==0)
    {
        printf("No readings provided");
        return 0;
    }
    float s=0;
    for (int i=0;i<c;i++)
    {
        s+=t[i];
    }
    printf("%.2f",s/c);
}
int main(){
    int n;
    scanf("%d",&n);
    int t[n];
    for (int i=0;i<n;i++){
        scanf("%d",t[i]);
    }
    avgt(n,t);
}