#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <functional>
#include <numeric>
#include <stack>
#include <queue>
#include <map>
#include <utility>

using namespace std;

#define FOR(i,a,b) for(long long int i=(a);i<(b);i++)
#define REP(i,N) for(long long int i=0;i<(N);i++)
#define ALL(s) (s).begin(),(s).end()

#define PI 3.14159265358479

typedef long long ll;

double a, b;

int main(){
	cin >> a >> b;
	printf("%10lf\n", a*b / 3.305785);
}