#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint1000000007;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000000000000

int main() {
    
	double p,q;
	cin>>p>>q;
	p/=100.0;
	q/=100.0;
	
	double ans = p*q;
	ans /= p*q + (1-p) * (1-q);
	ans *= 100.0;
	cout<<fixed<<setprecision(10)<<ans<<endl;
	
    return 0;
}