#include<bits/stdc++.h>
#define ll long long

using namespace std;
const int N = 1e4;
int n, m, t;
double p;

double check(int x)
{
    double a = 1.0 * x * n + m, b = 1 - pow(1 - p, x);
    return a / b;
}

void solve()
{
    cin >> n >> m >> t;
    p = 1.0 * t / N;
    int l = 1, r = 1e9;
    while (l < r)
    {
        int mid = l + r >> 1;
        if (check(mid) <= check(mid + 1))r = mid;
        else l = mid + 1;
    }
    printf("%.10lf\n",check(l));
}

int main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t; cin >> t;
    while (t--)solve();
    return 0;
}