#include<iostream>
#include<cctype>
#include<vector>
#include <ctype.h>
#include<algorithm>
#include<queue>
#include<string>
#include <math.h>
#include <iomanip>
using namespace std;
double a, b;
int main() {
	cin >> a >> b;
	cout << fixed<< setprecision(5)<<a*b/3.305785<< endl;
	return 0;
}
