#include <iostream>
#include <iomanip>

using namespace std;

int main()
{
    double a, b;
    const double tubo = 3.305785;

    cout << setprecision(6) << setiosflags(ios::fixed);
    while (cin >> a >> b) {
        cout << a * b / tubo << endl;
    }

    return 0;
}