main(t1)
{int t2,i,k;   
 int a[1000],totle;
 scanf("%d",&t1);
 while(t1--)
   {scanf("%d",&t2);
    for(i=0,totle=0;i<t2;i++)
      {scanf("%d",&a[i]);
       totle+=a[i];}
    for(i=0,k=0;i<t2;i++)
       if(a[i]*t2>totle)k++;
    printf("%.3f%%\n",k*1.0/t2*100);
   }
}