#include <bits/stdc++.h>
using namespace std;
int n, p, q;
int a[100000];
int b[100000];
double f(double x) {
  double y = 1.0;
  for (int i = 0; i < n; i++) {
    y = min(y, (1.0 - a[i] * x) / (double)b[i]);
  }
  return p * x + q * y;
}
int main() {
  scanf("%d %d %d", &n, &p, &q);
  int ma = 0;
  for (int i = 0; i < n; ++i) {
    scanf("%d %d", a + i, b + i);
    ma = a[i] > ma ? a[i] : ma;
  }
  double l, r, lmid, rmid;
  l = 0;
  r = 1.0 / ma;
  double eps = 1E-9;
  for (int i = 0; i < 50; ++i) {
    lmid = l + (r - l) / 3;
    rmid = lmid + (r - l) / 3;
    if (f(lmid) > f(rmid))
      r = rmid;
    else
      l = lmid;
  }
  printf("%f", f(l));
}
