#include <bits/stdc++.h>
using namespace std;
void readi(int &x) {
  int v = 0, f = 1;
  char c = getchar();
  while (!isdigit(c) && c != '-') c = getchar();
  if (c == '-')
    f = -1;
  else
    v = v * 10 + c - '0';
  while (isdigit(c = getchar())) v = v * 10 + c - '0';
  x = v * f;
}
void readll(long long &x) {
  long long v = 0ll, f = 1ll;
  char c = getchar();
  while (!isdigit(c) && c != '-') c = getchar();
  if (c == '-')
    f = -1;
  else
    v = v * 10 + c - '0';
  while (isdigit(c = getchar())) v = v * 10 + c - '0';
  x = v * f;
}
void readc(char &x) {
  char c;
  while ((c = getchar()) == ' ')
    ;
  x = c;
}
void writes(string s) { puts(s.c_str()); }
void writeln() { writes(""); }
void writei(int x) {
  if (x < 0) {
    putchar('-');
    x = abs(x);
  }
  if (!x) putchar('0');
  char a[25];
  int top = 0;
  while (x) {
    a[++top] = (x % 10) + '0';
    x /= 10;
  }
  while (top) {
    putchar(a[top]);
    top--;
  }
}
void writell(long long x) {
  if (x < 0) {
    putchar('-');
    x = abs(x);
  }
  if (!x) putchar('0');
  char a[25];
  int top = 0;
  while (x) {
    a[++top] = (x % 10) + '0';
    x /= 10;
  }
  while (top) {
    putchar(a[top]);
    top--;
  }
}
inline long long inc(int &x) { return ++x; }
inline long long inc(long long &x) { return ++x; }
inline long long inc(int &x, long long y) { return x += y; }
inline long long inc(long long &x, long long y) { return x += y; }
inline double inc(double &x, double y) { return x += y; }
inline long long dec(int &x) { return --x; }
inline long long dec(long long &x) { return --x; }
inline long long dec(int &x, long long y) { return x -= y; }
inline long long dec(long long &x, long long y) { return x -= y; }
inline double dec(double &x, double y) { return x -= y; }
inline long long mul(int &x) { return x = ((long long)x) * x; }
inline long long mul(long long &x) { return x = x * x; }
inline long long mul(int &x, long long y) { return x *= y; }
inline long long mul(long long &x, long long y) { return x *= y; }
inline double mul(double &x, double y) { return x *= y; }
inline long long divi(const int &x) {
  long long ans, l, r, mid;
  ans = 0;
  l = 0;
  r = 0x3fffffff;
  while (l < r) {
    mid = (l + r) / 2;
    if (mid * mid <= x) {
      ans = mid;
      l = mid + 1;
    } else
      r = mid;
  }
  return ans;
}
inline long long divi(const long long &x) {
  long long ans, l, r, mid;
  ans = 0;
  l = 0;
  r = 0x3fffffff;
  while (l < r) {
    mid = (l + r) / 2;
    if (mid * mid <= x) {
      ans = mid;
      l = mid + 1;
    } else
      r = mid;
  }
  return ans;
}
inline long long divi(int &x, long long y) { return x /= y; }
inline long long divi(long long &x, long long y) { return x /= y; }
inline double divi(double &x, double y) { return x /= y; }
inline long long mod(int &x, long long y) { return x %= y; }
inline long long mod(long long &x, long long y) { return x %= y; }
int n, m, i, j, x[55], y[55];
double l, r, mid, dp[55][55], sum[55];
vector<double> a[55];
vector<int> all;
bool check(double mid) {
  int i, j, k;
  if ((0) <= (54))
    for ((i) = (0); (i) <= (54); (i)++)
      if ((0) <= (54))
        for ((j) = (0); (j) <= (54); (j)++) dp[i][j] = 1e18;
  dp[all.size() + 1][0] = 0;
  for (i = all.size(); i >= 1; i--) {
    sum[a[i].size()] = 0;
    for (j = a[i].size() - 1; j >= 0; j--)
      sum[j] = sum[j + 1] - a[i][j] * mid + all[i - 1];
    for (j = 0; j + a[i].size() <= n; j++) {
      for (k = 0; k <= a[i].size() && k <= j; k++) {
        dp[i][j - k + a[i].size() - k] =
            min(dp[i][j - k + a[i].size() - k], dp[i + 1][j] + sum[k]);
      }
    }
  }
  for (i = 0; i <= n; i++)
    if (dp[1][i] <= 0) return 1;
  return 0;
}
int main() {
  cin >> n;
  for (i = 1; i <= n; i++) {
    cin >> x[i];
    all.push_back(x[i]);
  }
  stable_sort((all).begin(), (all).end());
  all.resize(unique((all).begin(), (all).end()) - all.begin());
  for (i = 1; i <= n; i++) {
    cin >> y[i];
    a[upper_bound((all).begin(), (all).end(), x[i]) - all.begin()].push_back(
        y[i]);
  }
  for (i = 1; i <= all.size(); i++) stable_sort((a[i]).begin(), (a[i]).end());
  l = 0;
  r = 1e12;
  if ((1) <= ((150)))
    for (((i)) = (1); ((i)) <= ((150)); ((i))++) {
      mid = (l + r) / 2;
      if (check(mid))
        r = mid;
      else
        l = mid;
    }
  printf("%I64d\n", (long long)((mid * 1000 + 0.99999999)));
  return 0;
}
