#include<bits/stdc++.h>
const int P = 998244353;
typedef long long ll;
#define rep(i,x,y) for (int i=(x);i<=(y);++i)
using namespace std;
void solve() {
	int n;
	cin >> n;
	double ans = 0;
	vector<ll> a(n + 1);
	rep(i, 1, n) cin >> a[i];
	rep(i, 1, n) {
		int l = i - 1;
		int r = i + 1;
		if (l >= 1 && r <= n && a[l] > a[i] && a[r] > a[i]) {
			ll sum = a[i];
			int cnt = 1;
			while (l >= 1 && a[l] > a[l + 1]) sum += a[l], cnt++, l--;
			while (r <= n && a[r] > a[r - 1]) sum += a[r], cnt++, r++;
			ans = max(ans, sum * 1.0 / cnt);
		}
	}
	cout << fixed << setprecision(20) << ans << '\n';
	return;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int t = 1;
	cin >> t;
	while (t--) solve();
	return 0;
}
/*
2
4
8 2 7 10
6
9 6 5 3 4 8
*/