#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define leftchild(i) (2*(i)+1)
void heapsort(double a[],int n);
void percdown(double a[],int i,int n);
int main(void)
{int T,n,i;
double a[1001];
scanf("%d",&T);
while(T--)
{scanf("%d",&n);
for(i=0;i<n;i++)
scanf("%lf",&a[i]);
heapsort(a,n);
if(n%2==1) printf("%.3lf\n",a[n/2]);
else printf("%.3lf\n",(a[n/2]+a[n/2-1])/2);
}
system("pause");
}
void percdown(double a[],int i,int n)
{double temp;
int child;
for(temp=a[i];leftchild(i)<n;i=child)
{child=leftchild(i);
if(child!=n-1&&a[child]<a[child+1])
child++;
if(temp<a[child])
a[i]=a[child];
else break;
}
a[i]=temp;
}
void heapsort(double a[],int n)
{
int i;
double temp;
for(i=n/2;i>=0;i--)
percdown(a,i,n);
for(i=n-1;i>0;i--)
{temp=a[0];a[0]=a[i];a[i]=temp;
percdown(a,0,i);
}
}