#include <iostream>
#include <iomanip>

using namespace std;

int main()
{
	double a, b;
	double menseki, tubo;
	
	cin >> a >> b;
	
	menseki = a * b;
	
	tubo = menseki / 3.305785;
	
	
	cout << setprecision(6);
	cout << setiosflags(ios::fixed);

	cout << tubo << endl;
	
	return 0;
	
}