#include <bits/stdc++.h>
#define rep(i,n) for(int i=1;i<=n;i++)
using namespace std;
using ll =  long long ;
using P = pair<int,int> ;
const int INF = 1e9;
const int MOD = 1000000007;

int main(){
    double p,q;
    cin >> p >> q;
    double ans = (p*q*100)/(double)(10000-100*p-100*q+2*p*q);
    cout << setprecision(12) << ans << endl;
    return 0;
}