#include <algorithm>
#include <iostream>
#include <iomanip>
#include <cstring>
#include <string>
#include <vector>
#include <random>
#include <bitset>
#include <queue>
#include <cmath>
#include <stack>
#include <set>
#include <map>
typedef long long ll;
typedef long double ld;
using namespace std;

ld dp[1005][1005];
// i->j->iとなる確率

int main() {
    int n;
    ld p, q;
    cin >> n >> p >> q;

    if (q == 0.0) {
        cout << p << "\n";
        return 0;
    }

    for (int i = 0; i < n; i++) dp[i][i] = p / (q * q);
    for (int d = 1; d < n; d++) {
        for (int i = 0; i < n; i++)  {
            ld tmp = 0.0;
            for (int k = i + 1; k < i + d; k++) tmp += q * q * dp[i+1][k];
            dp[i][i+d] = q * q * dp[i+1][i+d] / (1.0 - tmp);
        }
    }

    ld ans = 0.0;
    for (int i = 0; i < n; i++) ans += q * q * dp[0][i];

    cout << ans << "\n";
    return 0;
}