#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <cstring>
#include <fstream>
#include <numeric>
#include <algorithm>
#include <cstdio>

using namespace std;

int main(int argc, char **argv) {
  int a, b;
  long double tubo;
  const long double rate = 3.305785L;

  cin >> a >> b;
  tubo = a * b / rate;
  printf("%.6Lf\n", tubo);
  return 0;
}