#include <iostream>
using namespace std;

int main() {
    int x, y;
    cin >> x >> y;
    int unit_price = y / x;
    int total_price = 5 * unit_price;
    cout << total_price << endl;
    return 0;
}    
/**************************************************************
	Problem: 1417
	User: linmiaoling
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/