#include <sstream>
#include <string>
#include <vector>
#include <map>
#include <algorithm>
#include <iostream>
#include <utility>
#include <set>
#include <cctype>
#include <queue>
#include <stack>
#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;
#define INF 100000000
typedef long long ll;

int main(void) {
    double a, b;
    cin >> a >> b;
    printf("%.7f\n", a*b/3.305785);
    return 0;
}