#include <bits/stdc++.h>
using namespace std;
int main() {
  cin.tie(0);
  ios_base::sync_with_stdio(false);
  int n, p, q;
  cin >> n >> p >> q;
  vector<int> a(n), b(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i] >> b[i];
  }
  double l = 0.0, r = 1.0e+10;
  for (int i = 0; i < n; ++i) {
    if (1LL * p * b[i] == 1LL * q * a[i]) {
      r = min(r, 1.0 * p / a[i]);
    }
  }
  for (int i = 0; i < 70; ++i) {
    double m = (l + r) * 0.5;
    double pl = 0.0, pr = m / p;
    for (int j = 0; j < n; ++j) {
      if (1LL * p * b[j] == 1LL * q * a[j]) continue;
      double pos = (b[j] * m - q) / (1LL * b[j] * p - 1LL * a[j] * q);
      if (1LL * p * b[j] > 1LL * q * a[j]) {
        pl = max(pl, pos);
      } else {
        pr = min(pr, pos);
      }
    }
    if (pl > pr)
      r = m;
    else
      l = m;
  }
  cout << fixed << setprecision(15) << l << endl;
  return 0;
}
