using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using static System.Console;
using static System.Math;

namespace AtTest.yukicoder
{
    class _813
    {
        static void Main(string[] args)
        {
            Method(args);
        }

        static void Method(string[] args)
        {
            int n = ReadInt();
            double p = ReadDouble();
            double q = ReadDouble();
            if (p == 1)
            {
                WriteLine(1);
                return;
            }
            if (q == 1)
            {
                WriteLine(0);
                return;
            }

            double back = p;
            double go=q;
            for(int i = 1; i < n; i++)
            {
                back = back + p * go * go / (1 - back * p);
                go = go * q / (1 - back * p);
            }
            WriteLine(back);
        }

        private static string Read() { return ReadLine(); }
        private static char[] ReadChars() { return Array.ConvertAll(Read().Split(), a => a[0]); }
        private static int ReadInt() { return int.Parse(Read()); }
        private static long ReadLong() { return long.Parse(Read()); }
        private static double ReadDouble() { return double.Parse(Read()); }
        private static int[] ReadInts() { return Array.ConvertAll(Read().Split(), int.Parse); }
        private static long[] ReadLongs() { return Array.ConvertAll(Read().Split(), long.Parse); }
        private static double[] ReadDoubles() { return Array.ConvertAll(Read().Split(), double.Parse); }
    }
}