#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1.0);
const long long mod = 1e9 + 7;
const int N = 100010;
int main() {
  double l, p, q;
  while (~scanf("%lf%lf%lf", &l, &p, &q)) {
    printf("%.4lf\n", l / (p + q) * p);
  }
  return 0;
}
