//#pragma GCC target("avx2")
//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")
#include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <complex>
#include <deque>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <tuple>
#include <vector>
using namespace std;
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using pli = pair<ll,int>;
#define TEST cerr << "TEST" << endl
#define AMARI 998244353
//#define AMARI 1000000007
#define el '\n'
#define El '\n'
#define eps 1e-6

#define MULTI_TEST_CASE false 
void solve(void){
    cout << fixed << setprecision(15);
    int n;
    cin >> n;
    long double p,q;
    cin >> p >> q;
    if(abs(1 - p) <= eps){
        cout << 1 << el;
        return;
    }
    long double lp = 0,lq = 1;
    for(int i = 0; i < n; i++){
        long double p1 = lp,p2 = p,q1 = lq,q2 = q;
        lp = p1 + (q1 * q1 * p2 / (1 - p1 * p2));
        lq = q1 * q2 / (1 - p1 * p2);
    }
    cout << lp << el;
    return;
}

void calc(void){
    return;
}

signed main(void){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    calc();
    int t = 1;
    if(MULTI_TEST_CASE)cin >> t;
    while(t--){
        solve();
    }
    return 0;
}