#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;
		double t;
		scanf("%d%d%lf", &a, &b, &t);
		//a log n + b log log n = log t
		auto logt = log(round(t * 1e4) * 1e-4L);
		auto x = 2.L;
		if(a == 0) {
			x = exp(pow(t * 1.L, 1.L / b));
		} else if(b == 0) {
			x = pow(t * 1.L, 1.L / a);
		} else {
			double y = x - 1;
			rep(k, 20) {
				auto logx = log1p(y);
				if(abs(a * logx + b) <= 1e-13)
					break;
				auto sub = ((y + 1) * logx * (a * logx + b * log(logx) - logt)) / (a * logx + b);
				if(abs(sub) <= 1e-15)
					break;
				y -= sub;
				amax(y, 1e-13L);
			}
			x = y + 1;
		}
		printf("%.10f\n", (double)x);
	}
	return 0;
}