#include <iostream>
#include <iomanip>
#include <vector>
#include <complex>
#include <cmath>
#include <algorithm>
#include <map>
#define shosu(x) fixed<<setprecision(x)
using namespace std;
int main(){
	cout<<shosu(6);
	int a,b;
	cin>>a>>b;
	cout<<a*b/3.305785<<endl;
}