#include <iostream>
#include <iomanip>

using ldouble = long double;

void solve() {
    ldouble p, q;
    std::cin >> p >> q;

    std::cout << std::fixed << std::setprecision(13)
              << p * q / (p * q + (100 - p) * (100 - q)) * 100
              << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}