program treec;
 var t,loop,x,y,w,i,ans,road,n,k:longint;
     l,max:real;
     a:array[0..1000,0..1000]of longint;
     f:array[0..1000]of longint;
  begin
   assign(input,'treec.in');
   reset(input);
   assign(output,'treec.out');
   rewrite(output);
   read(t);
   for loop:=1 to t do
    begin
     fillchar(f,sizeof(f),255);
     fillchar(a,sizeof(a),0); 
     read(n);
     for i:=1 to n-1 do 
      begin
       read(x,y,w);
       f[y]:=x;
       a[x,y]:=w;
      end;
     f[0]:=-2; 
     max:=0;
     for i:=1 to n do
      begin
       k:=i;
       ans:=0;
       road:=0;
       l:=0;
       while f[k]<>-2 do
        begin
         inc(ans);
         inc(road,a[f[k],k]);
         k:=f[k];
         if k=-1 then 
          begin
           ans:=0;
           road:=0;
          end;
        end;
       if ans<>0 then l:=road/ans;
       if l>max then max:=l;
      end;
     writeln(max:0:2);
    end; 
   close(input);
   close(output);
  end.