#include<iostream>
#include<cstdio>
#include<string>
#include<cmath>
#define loop(i,a,b) for(int i=a;i<b;i++)
#define rep(i,a) loop(i,0,a)
using namespace std;
int main(){
  int a,b;
  cin>>a>>b;
  a*=b;
  printf("%.20f\n",a/3.305785);
}