#include<iostream>
#include<iomanip>
#include<algorithm>
#include<cctype>
#include<cmath>
#include<cstdio>
#include<set>
#include<stack>
#include<string>
#include<sstream>
#include<map>
#include<queue>
#include<vector>
using namespace std;

double t = 3.305785;

int main() {
	int a, b;
	cin >> a >> b;
	double S = a*(b / t);
	cout << fixed << setprecision(6);
	cout << S << endl;

	return 0;
}