#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;
using ll = long long;

#include<iomanip>
int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    long double p,q;
    cin>>p>>q;
    long double pp = (long double) p / 100;
    long double qq = (long double) q / 100;
    long double sum = pp * qq + (1-pp) * (1-qq);
    long double ans = pp * qq / sum;
    ans *= 100;
    cout<<setprecision(30)<<fixed<<ans<<endl;
}