#include <bits/stdc++.h>
using namespace std;
using lint = long long int;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i<i##_end_;i++)
#define IFOR(i, begin, end) for(int i=(end)-1,i##_begin_=(begin);i>=i##_begin_;i--)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
template<typename T> istream &operator>>(istream &is, vector<T> &vec){ for (auto &v : vec) is >> v; return is; }
template<typename T> ostream &operator<<(ostream &os, const vector<T> &vec){ os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const deque<T> &vec){ os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa){ os << "(" << pa.first << "," << pa.second << ")"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template<typename T> void ndarray(vector<T> &vec, int len) { vec.resize(len); }
template<typename T, typename... Args> void ndarray(vector<T> &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) ndarray(v, args...); }
template<typename T> bool mmax(T &m, const T q) { if (m < q) {m = q; return true;} else return false; }
template<typename T> bool mmin(T &m, const T q) { if (m > q) {m = q; return true;} else return false; }
template<typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template<typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
#define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl;
#define FI first
#define SE second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((lint)(x).size())
#define POW2(n) (1LL << (n))

// vector<vector<double>> gauss_jordan(vector<vector<double>> mtr, double eps)
// {
//     // Gauss-Jordan elimination 行基本変形のみを用いるガウス消去法
//     int H = mtr.size(), W = mtr[0].size(), c = 0;
//     REP(h, H)
//     {
//         if (c == W) break;
//         int piv = -1;
//         FOR(j, h, H) if (abs(mtr[j][c]) > eps)
//         {
//             if (piv == -1 or abs(mtr[j][c]) > abs(mtr[piv][c])) piv = j;
//         }
//         if (piv == -1) { c++; h--; continue; }
//         swap(mtr[piv], mtr[h]);
//         if (h != piv) REP(w, W) mtr[piv][w] *= -1; // 行列式符号不変
//         double pivinv = 1.0 / mtr[h][c];
//         FOR(hh, h + 1, H) IFOR(w, c, W) mtr[hh][w] = mtr[hh][w] - mtr[h][w] * mtr[hh][c] * pivinv;
//         c++;
//     }
//     return mtr;
// }

vector<vector<double>> matmul(const vector<vector<double>> &A, const vector<vector<double>> &B)
{
    int H = A.size(), W = B[0].size(), K = B.size();
    vector<vector<double>> C(H, vector<double>(W));
    REP(i, H) REP(j, W) REP(k, K) (C[i][j] += A[i][k] * B[k][j]);
    return C;
}
vector<vector<double>> matpower(vector<vector<double>> X, lint n)
{
    vector<vector<double>> res(X.size(), vector<double>(X.size()));
    REP(i, res.size()) res[i][i] = 1;
    while (n)
    {
        if (n & 1) res = matmul(res, X);
        X = matmul(X, X); n >>= 1;
    }
    return res;
}

int main()
{
    int N;
    double p, q;
    cin >> N >> p >> q;

    if (q < 1e-10) cout << p << endl;
    else
    {
        vector<vector<double>> mat{{1 / q, -p / q}, {p / q, q - p * p / q}};

        vector<vector<double>> acc{{1, 0}, {0, 1}};
        REP(_, N)
        {
            acc = matmul(mat, acc);
            double su = 0;
            for (auto &vec : acc) for (auto &val : vec) su += val;
            for (auto &vec : acc) for (auto &val : vec) val /= su;;
        }
        cout << acc[1][0] / acc[0][0] << endl;
    }
}