#include <algorithm>
#include <cassert>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <iostream>
#include <tuple>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <ranges>
#include <iomanip>
using namespace std;
using ll = long long;

auto range(int n) { return views::iota(0, n); }

template<class T, class U> ostream& operator<<(ostream& os, const pair<T, U>& p){ return os << "{" << p.first << ", " << p.second << "}"; }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& obj) { os << "{"; for (const auto& e : obj) os << e << ", "; return os << "}"; }
template<typename T> ostream& operator<<(ostream& os, const set<T>& obj) { os << "set{"; for (const auto& e : obj) os << e << ", "; return os << "}"; }
template<typename T, typename U> ostream& operator<<(ostream& os, const map<T, U>& obj) { os << "map{"; for (const auto& e : obj) os << e << ", "; return os << "}"; }

#ifdef ONLINE_JUDGE
#define dump(expr) ;
#else
#define dump(expr) { cerr << "\033[33m#L" << __LINE__ << ": " << expr << "\033[39m" << endl; }
#endif

double solve() {
  int n; double p, q; cin >> n >> p >> q;
  vector<double> x(n + 1), y(n + 1);
  y[0] = 1;

  for (int it : range(50000)) {
    for (int i : range(n)) {
      x[i] = p * y[i] + q * x[i + 1];
      if (i > 0) y[i] = p * x[i] + q * y[i - 1];
    }
    for (int i = n - 1; i >= 0; --i) {
      x[i] = p * y[i] + q * x[i + 1];
      if (i > 0) y[i] = p * x[i] + q * y[i - 1];
    }

    if (it % 1000 == 0) dump(x[0]);
  }

  return x[0];
}

int main() {
  cout << fixed << setprecision(12);
  cout << solve() << endl;
}