#include <bits/stdc++.h>

using namespace std;

#define tubo 3.305785
 
double ans(int a, int b)
{
    return (a * b) / tubo; 
}
 
int main()
{
    int a, b;
    cin >> a >> b;
    printf("%.6f\n", ans(a, b));
    return 0;
}