#include<deque>
#include<list>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<vector>
#include<algorithm>
#include<string>
#include<iostream>
#include<numeric>
#include<cmath>
#include<cstdio>
#include<cstring>
using namespace std;
int main(){
  int p,q;
  cin>>p>>q;
  printf("%.5f\n",p*q/3.305785);
  return 0;
}