/**
 *   @FileName	a.cpp
 *   @Author	kanpurin
 *   @Created	2020.06.12 01:44:19
**/

#include "bits/stdc++.h" 
using namespace std; 
typedef long long ll;

int main() {
    double p,q;cin >> p >> q;
    printf("%.10f\n",(double)p*q/(p*q+(100-p)*(100-q))*100);
    return 0;
}