#include using namespace std; using uint = unsigned int; using lint = long long int; using ulint = unsigned long long int; template using V = vector; template using VV = V< V >; template void assign(V& v, int n, const U& a) { v.assign(n, a); } template void assign(V& 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'; }