#include <iostream>
#include <iomanip>
#include <vector>
#include <set>
#include <algorithm>
#include <string>
#include <sstream>
 
#define INPUT_FROM_FILE (0) 
#if INPUT_FROM_FILE
#include <fstream>
#endif

int main(int argc, char **argv){
	int a, b;
	bool is_first = true;
	double area_t = 0;

#if INPUT_FROM_FILE
	std::ifstream ifs("test.txt");
	//FILE *fp = fopen("test.txt", "r");
#endif

#if INPUT_FROM_FILE
	ifs >> a >> b;
#else
	std::cin >> a >> b;
#endif

	area_t = a * b / 3.305785;

	printf("%.6lf\n", area_t);
 
#if INPUT_FROM_FILE
	//fclose(fp);
#endif
    return 0;
}
