#include #include #include #include #include #include #include #include #include #include #include static const int MOD = 1000000007; using ll = long long; using u32 = uint32_t; using namespace std; template constexpr T INF = ::numeric_limits::max()/32*15+208; int main() { double p, q; cin >> p >> q; printf("%.10f", 100*p*q/(p*q+(100-p)*(100-q))); return 0; }