#include <iostream>
#include <stdio.h>

using namespace std;


int main(){
	int n, m, in;

	cin >> n;

	for(int i = 0; i < n; i++){
		cin >> m;
		int arr[m];
		double ave = 0;
		double percent = 0;

		for(int j = 0; j < m; j++){
			cin >> in;
			arr[j] = in;
			ave += in;
		}

		ave = ave/m;

		// cout << ave << endl;
		for(int j = 0; j < m; j++){
			if(arr[j] > ave){
				percent++;
			}
		}

		percent = percent/m;

		printf("%.3f%%\n", percent * 100);
		
	}
	return 0; 

}