#include <cstdio>
#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

const long long MAX = 5100000;
const long long INF = 1LL << 60;
const long long mod = 1000000007LL;
//const long long mod = 998244353LL;

using namespace std;
typedef unsigned long long ull;
typedef long long ll;



int main()
{
	/*
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	*/
	ll N; scanf("%lld", &N);
	double p, q; cin >> p >> q;
	double np = p;
	double nq = q;
	if (abs(p - 1) < 1e-7) {
		puts("1");
		return 0;
	}
	for (ll i = 1; i < N; i++) {
		double tp = np + nq * nq * p / (1 - np * p);
		double tq = nq * q / (1 - np * p);
		np = tp;
		nq = tq;
	}
	cout << fixed << setprecision(12) << np << endl;
	return 0;
}