#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,y;
    cin>>n>>y;
    cout<<(y/n)*5;
	 
	return 0;
}

/**************************************************************
	Problem: 1417
	User: duyahan
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/