#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <math.h>
#include <functional>
#include <algorithm>
#include <utility>

typedef long long Int;
#define REP(i,n) for(int i = 0 ; i < n ; ++i)
#define REPS(a,i,n) for(int i = a ; i < n ; ++i)
using namespace std;

int main(){
	double a, b;
	cin >> a >> b;

	printf("%.6lf\n", a*b / 3.305785);
	return 0;
}