#include <bits/stdc++.h>
using namespace std;
const long long inf = 0x3f3f3f3f;
const long long INF = 0x3f3f3f3f3f3f3f3fLL;
const long long mod = 1e9 + 7;
long long powmod(long long a, long long b) {
  long long res = 1;
  a %= mod;
  assert(b >= 0);
  for (; b; b >>= 1) {
    if (b & 1) res = res * a % mod;
    a = a * a % mod;
  }
  return res;
}
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
long long pct(long long x) { return __builtin_popcount(x); }
long long bit(long long x) { return 31 - __builtin_clz(x); }
long long cdiv(long long a, long long b) {
  return a / b + !(a < 0 || a % b == 0);
}
void DBG() { cerr << "]" << endl; }
template <class H, class... T>
void DBG(H h, T... t) {
  cerr << to_string(h);
  if (sizeof...(t)) cerr << ", ";
  DBG(t...);
}
const long long maxn = 1e5 * 3 + 20;
long long n, _, q, k;
long long T;
long double eps = 1e-12;
void solve() {
  cin >> n >> T;
  vector<long long> lim(n);
  vector<long long> tp(n);
  bool hasless = false;
  bool haslarger = false;
  long long tt = 0;
  for (signed i = 0; i < n; i++) {
    cin >> lim[i];
    tt += lim[i];
  }
  for (signed i = 0; i < n; i++) {
    cin >> tp[i];
    if (tp[i] >= T) haslarger = true;
    if (tp[i] <= T) hasless = true;
  }
  if (!hasless || !haslarger) {
    cout << (0) << endl;
    exit(0);
  }
  long double ans = 0;
  vector<pair<long long, long long> > lf;
  vector<pair<long long, long long> > rt;
  long long lsm = 0;
  long long rsm = 0;
  for (signed i = 0; i < n; i++) {
    long long c = tp[i] - T;
    if (c == 0) {
      ans += ((long double)lim[i]);
    } else {
      if (c > 0) {
        lf.emplace_back(c, lim[i]);
        lsm += (c * lim[i]);
      } else {
        rt.emplace_back(-c, lim[i]);
        rsm += ((-c) * lim[i]);
      }
    }
  }
  if (lsm > rsm) {
    swap(lf, rt);
    swap(lsm, rsm);
  }
  if (lsm == rsm) {
    cout << fixed << setprecision(13) << (long double)tt << endl;
    exit(0);
  }
  for (auto p : lf) {
    ans += p.second;
  }
  sort(begin(rt), end(rt));
  long double rem = lsm;
  for (signed i = 0; i < (signed)rt.size(); i++) {
    long double useall = rt[i].first * rt[i].second;
    if (rem - useall >= eps) {
      rem -= useall;
      ans += rt[i].second;
    } else {
      long double could = rem / (long double)rt[i].first;
      ans += could;
      rem = 0;
    }
  }
  cout << fixed << setprecision(13) << ans << endl;
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  solve();
  return 0;
}
