#include<bits/stdc++.h>
using namespace std;
int main(){
	int x,y;
	cin>>x>>y;
	int h=(y/x)*5;
	cout<<h;
	return 0;
}
/**************************************************************
	Problem: 1417
	User: fuhoubin
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:2072 kb
****************************************************************/