#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
using mint = atcoder::modint1000000007;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll N;
    cin >> N;

    vector<ll> A(N), B(N);
    for (auto &x : A) cin >> x;
    for (auto &x : B) cin >> x;

    vector<pair<pair<ll,ll>, ll>> V;
    // {{分子B, 分母A}, 重み|A|}

    for (int i = 0; i < N; i++) {
        if (A[i] == 0) continue;

        ll a = A[i];
        ll b = B[i];

        if (a < 0) {
            a = -a;
            b = -b;
        }

        V.push_back({{b, a}, a});
    }

    sort(V.begin(), V.end(), [](auto x, auto y) {
        auto [b1, a1] = x.first;
        auto [b2, a2] = y.first;

        __int128 left = (__int128)b1 * a2;
        __int128 right = (__int128)b2 * a1;
        return left < right;
    });

    ll total = 0;
    for (auto &e : V) total += e.second;

    ll cum = 0;
    pair<ll,ll> ans = {0, 1};

    for (auto &e : V) {
        cum += e.second;

        if (cum * 2 >= total) {
            ans = e.first;
            break;
        }
    }

    ll num = ans.first;
    ll den = ans.second;

    mint res = mint(num) / mint(den);
    cout << res.val() << '\n';

    return 0;
}