#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007;
struct fraction{
  long long a, b;
  fraction(){
  }
  fraction(long long a, long long b): a(a), b(b){
  }
  bool operator <(fraction x) const{
    return a * x.b < x.a * b;
  }
};
int main(){
  int N;
  cin >> N;
  vector<int> A(N);
  for (int i = 0; i < N; i++){
    cin >> A[i];
  }
  vector<int> B(N);
  for (int i = 0; i < N; i++){
    cin >> B[i];
  }
  vector<pair<fraction, int>> P(N);
  for (int i = 0; i < N; i++){
    P[i] = make_pair(fraction(A[i], 1 + B[i]), i);
  }
  sort(P.begin(), P.end());
  long long ans = 0;
  long long x = 1;
  for (int i = 0; i < N; i++){
    int p = P[i].second;
    ans += x * A[p] % MOD;
    x *= B[p];
    x %= MOD;
  }
  ans %= MOD;
  cout << ans << endl;
}