#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t;
  cin >> t;
  while (t--) {
    long long s, a, b, c;
    cin >> s >> a >> b >> c;
    long long bars = s / c;
    bars += (bars / a) * b;
    cout << bars << endl;
  }
}
