#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using pii = pair<int, int>;

int main() {
  cin.tie(0);
  ios_base::sync_with_stdio(false);
  cout << fixed << setprecision(10);
  
  int a, b;
  cin >> a >> b;
  cout << a * b / 3.305785 << endl;

  return 0;
}
