#include <bits/stdc++.h> using namespace std; using uint = unsigned int; using lint = long long int; using ulint = unsigned long long int; template<class T = int> using V = vector<T>; template<class T = int> using VV = V< V<T> >; template<class T, class U> void assign(V<T>& v, int n, const U& a) { v.assign(n, a); } template<class T, class... Args> void assign(V<T>& v, int n, const Args&... args) { v.resize(n); for (auto&& e : v) assign(e, args...); } int main() { cin.tie(nullptr); ios_base::sync_with_stdio(false); long double p, q; cin >> p >> q; p /= 100; q /= 100; long double r = p * q / ((1 - p) * (1 - q) + p * q); cout << fixed << setprecision(15) << 100 * r << '\n'; }