#include<cstdio>
#include<iostream>
#include<cmath>
#include<vector>
#include<string>
#include<algorithm>

#define ll long long
#define LL long long
#define ULL unsigned long long 
#define ull unsigned long long 
#define FOR(i,a,b) for(int i=a;i<b;i++)
#define RFOR(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define REP(i,n) for(int i=0;i<n;i++)
#define RREP(i,n) for(int i=(n)-1;i>=0;i--)


using namespace std;

int main()
{

	double a, b, tmp,ans;
	cin >> a >> b;
	ans = a*b;
	ans /= 3.305785;
	printf("%f\n", ans);
	return 0;
}