#include<bits/stdc++.h>
#include<vector>
#include<list>
#include<stack>
#include<queue>
#include<algorithm>
using namespace std;


int main(){
    int a,b;
    double t=3.305785; 
    scanf("%d %d",&a,&b);
    printf("%.10lf\n",a*b/t);
    return 0;
}