#include <iostream>
#include <vector>

using namespace std;

vector<int> v;

int main() {
    int a,b,c,e = 0;
    double d = 0;

    cin >> a;
    for (int i = 0; i < a; i++) {
        cin >> b;
        for (int i = 0; i < b; i++) {
            cin >> c;
            d = d + c;
            v.push_back(c);
        }
        d = d / b;

        for (int i = 0; i < b; i++){
            if (v[i] > d) {
                e++;
            }
        }
        cout << fixed;
        cout.precision(3);
        cout << 100 * double(e) / b << endl;

        d = 0;
        e = 0;
        v.resize(0);
    }
}