text: // Problem :    https://exercise.acmcoder.com/online/online_judge_ques?ques_id=1685&konwledgeId=140
  // Solution:    https://github.com/tjzhym/ACMcoder
  // Author :     zhym (tjzhym)
  // Date   :     2021-8-11
  
  
  #include <iostream>
  #include<iomanip>
  using namespace std;
  
  int main() {
      double n = 0.0, m = 0.0, x = 0.0;
      int p = 0, q = 0;
      double chooseNumber = 0.0;
      cin >> n >> m >> x;
      cin >> p >> q;
  
      chooseNumber = (p * x) / ((n + 1) * q - p * n);
  
      if (chooseNumber > m) {
          chooseNumber = m;
      }
      else if (chooseNumber < 1) {
          chooseNumber = 1;
      }
      cout << fixed << setprecision(2) << chooseNumber;
      return 0;
  }