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

using namespace std;

const int N = 1e5 + 7;
const double esp = 1e-7;
int n,m,k;
int a[N],b[N];
double p;

double check(double x){
    return (x * n + m) / (1 - pow(1 - p,x));
}

void solve(){
    cin >> n >> m;
    cin >> p;
    p /= 1e4;
    double l = 1,r = 1e9;
    while(r - l > esp){
        double cnt = (r - l) / 3.0;
        double mid1 = l + cnt;
        double mid2 = r - cnt;
        if(check(mid1) < check(mid2)){
            r = mid2;
        } else{
            l = mid1;
        }
    } double ans = check(l);
    printf("%.10lf\n",ans);
}

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