#include <bits/stdc++.h>
using namespace std;
int a[100000], b[100000];
int n;
long long p, q;
bool ok(long double val) {
  long double l = 0, r = val / p, num, den;
  for (int i = 0; i < n; i++) {
    den = a[i] * q - b[i] * p;
    if (a[i] * q > b[i] * p)
      r = min(r, (q - b[i] * val) / (a[i] * q - b[i] * p));
    else if (a[i] * q < b[i] * p)
      l = max(l, (q - b[i] * val) / (a[i] * q - b[i] * p));
    else if (val * b[i] > q)
      return 0;
    if (l > r) return 0;
  }
}
int main() {
  cin >> n >> p >> q;
  for (int i = 0; i < n; i++) scanf("%d%d", a + i, b + i);
  long double low = 0, high = p + q, mid;
  while (high - low > 1e-7) {
    mid = (high + low) / 2;
    if (ok(mid))
      low = mid;
    else
      high = mid;
  }
  printf("%.9f\n", (double)high);
}
