#include<iostream>
#include<iomanip>
#include<algorithm>
using namespace std;
double p0,q;
double ans=1./3;
void dfs(double w,double p)
{
	if(w<1e-10)return;
	ans+=w*(p/2+(1-p)/3);
	dfs(w*p/2,max(p-q,0.));
	dfs(w*(1-p)/3,min(p+q,1.));
}
main()
{
	cin>>p0>>q;
	p0/=100;
	q/=100;
	dfs(1./3,p0);
	cout<<fixed<<setprecision(16)<<ans<<endl;
}