#include <iostream>
#include <iomanip>
#include <cstdint>
#include <cstdio>
#include <math.h>

using namespace std;

int main() {
    int V_field;
    int V_forest;
    cin >> V_field >> V_forest;

    long double border;
    cin >> border;

    long double L = 0;
    long double R = 1;

    while (R - L > 0.000001) {
        long double a = (L * 2 + R) / 3;
        long double b = (L + R * 2) / 3;
        long double a_time = sqrt(a * a + (1 - border) * (1 - border)) / V_field +
                             sqrt((1 - a) * (1 - a) + border * border) / V_forest;
        long double b_time = sqrt(b * b + (1 - border) * (1 - border)) / V_field +
                             sqrt((1 - b) * (1 - b) + border * border) / V_forest;
        if (a_time < b_time) {
            R = b;
        }
        else {
            L = a;
        }
    }

    cout << fixed << setprecision(13) << (L + R) / 2 << endl;

    return 0;
}