#include "bits/stdc++.h"
using namespace std;
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
static const int INF = 0x3f3f3f3f; static const long long INFL = 0x3f3f3f3f3f3f3f3fLL;
typedef vector<int> vi; typedef pair<int, int> pii; typedef vector<pair<int, int> > vpii; typedef long long ll;
template<typename T, typename U> static void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> static void amax(T &x, U y) { if(x < y) x = y; }

int main() {
	int T;
	scanf("%d", &T);
	rep(ii, T) {
		int a, b;
		long double t;
		scanf("%d%d%Lf", &a, &b, &t);
		//a log n + b log log n = log t
		auto logt = log(t);
		auto x = max(2.L, min(exp(logt / a), exp(exp(logt / b))));
		rep(k, 10) {
			auto logx = log(x);
			x -= (x * logx * (a * logx + b * log(logx) - logt)) / (a * logx + b);
			x = max(x, 1.L+1e-13);
		}
		printf("%.20Lf\n", x);
	}
	return 0;
}