#include <bits/stdc++.h>
using namespace std;

#define iota(i,n,b,s) for(int i=int(b);i!=int((b)+(s)*(n));i+=(s))
#define range(i,n,m) iota(i,(((n)>(m))?((n)-(m)):((m)-(n))),(n),((n)>(m)?-1:1))
#define rep(i,n) iota(i,(n),0,1)
#define loop for(;;)

#define INF (1e9)
#define EPS (1e-9)
#define cons(a,b) (make_pair(a,b))
#define car(a) (a.first)
#define cdr(a) (a.second)
#define cadr(a) (car(cdr(a)))
#define cddr(a) (cdr(cdr(a)))
#define all(a) a.begin(), a.end()
#define trace(var) cerr<<">>> "<<#var<<" = "<<var<<endl;

typedef long long Integer;
typedef long double Real;
typedef vector<int> vi;
typedef vector<string> vs;
typedef map<string,int> Dictionary;
const Real PI = acos(-1);

template<class S, class T>
ostream& operator<<(ostream& os, pair<S,T> p) {
  os << '(' << car(p) << ", " << cdr(p) << ')';
  return os;
}

template<class T>
ostream& operator<<(ostream& os, vector<T> v) {
  if (v.size() == 0) {
    os << "(empty)";
    return os;
  }
  os << v[0];
  for (int i=1, len=v.size(); i<len; ++i) os << ' ' << v[i];
  return os;
}

int dx[] = { -1, 0, 1, 0 };
int dy[] = {  0, -1, 0, 1 };

char u[] = {'I', 'V', 'X', 'L', 'C', 'D', 'M'};
int v[] =  {1, 5, 10, 50, 100, 500, 1000};

int value_of (char c) {
  rep (i, 7) {
    if (c == u[i]) return v[i];
  }
}

int div(int a, int b, int n) {
  a %= b;
  a = a * 10;
  if (n == 1) return (a/b);
  return div(a, b, n - 1);
}
bool* PrimeSieve(int n) {
  bool*s = new bool[n];
  for (int i = 0; i < n; ++i) s[i] = true;
  s[0] = s[1] = false;
  for (int i = 2; i < n; ++i)
    if (s[i]) for (int j = i << 1; j < n; j += i) s[j] = false;
  return s;
}

int main() {

  Real a, b;
  cin >> a >> b;
  printf("%0.10Lf\n", (a * b / 3.305785));

  return 0;
}