#include <bits/stdc++.h>
using ll = long long;
using ld = long double;
template <typename T>
constexpr T MOD() { return 1000000007; }
template <typename T>
constexpr T INF() { return std::numeric_limits<T>::max() / 16; }
int main()
{
    ll P, Q;
    std::cin >> P >> Q;
    std::cout << std::fixed << std::setprecision(15) << (ld)(100 * P * Q) / (P * Q + (100 - P) * (100 - Q)) << std::endl;
    return 0;
}