#include<iostream>
#include<iomanip>

using namespace std;

int main() {
	
	int a, b;
	
	while(cin >> a >> b) {
		
		double ans = 0;
		ans = a * b / 3.305785;
		cout << fixed << setprecision(6) << ans << "\n";
		
	}
	
	return 0;
}

