package main

import (
	"bufio"
	"os"
	"strconv"
	"fmt"
	"math"
)

type Scanner struct {
	r   *bufio.Reader
	buf []byte
	p   int
}

func NewScanner() *Scanner {
	rdr := bufio.NewReaderSize(os.Stdin, 1000)
	return &Scanner{r:rdr}
}
func (s *Scanner) Next() string {
	s.pre()
	start := s.p
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			break
		}
	}
	result := string(s.buf[start:s.p])
	s.p++
	return result
}
func (s *Scanner) NextLine() string {
	s.pre()
	start := s.p
	s.p = len(s.buf)
	return string(s.buf[start:])
}
func (s *Scanner) NextInt() int {
	v, _ := strconv.Atoi(s.Next())
	return v
}

func (s *Scanner) NextIntArray() []int {
	s.pre()
	start := s.p
	result := []int{}
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			v, _ := strconv.Atoi(string(s.buf[start:s.p]))
			result = append(result, v)
			start = s.p + 1
		}
	}
	v, _ := strconv.Atoi(string(s.buf[start:s.p]))
	result = append(result, v)

	return result
}

func (s *Scanner) NextMap() map[int]bool {
	s.pre()
	start := s.p
	mp := map[int]bool{}
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			v, _ := strconv.Atoi(string(s.buf[start:s.p]))
			mp[v] = true
			start = s.p + 1
		}
	}
	v, _ := strconv.Atoi(string(s.buf[start:s.p]))
	mp[v] = true

	return mp
}

func (s *Scanner) pre() {
	if s.p >= len(s.buf) {
		s.readLine()
		s.p = 0
	}
}
func (s *Scanner) readLine() {
	s.buf = make([]byte, 0)
	for {
		l, p, e := s.r.ReadLine()
		if e != nil {
			panic(e)
		}
		s.buf = append(s.buf, l...)
		if !p {
			break
		}
	}
}

func recv(cur, p, q float64, turn int) float64 {
	if turn > 20 {
		return 0
	}
	result := 0.0
	// 必勝法を使って勝つ
	result += p * cur * 0.5

	// 必勝法を使ってあいこになる
	result += recv(p * cur * 0.5, math.Max(0, p - q), q, turn + 1)

	// 必勝法を使わず勝つ
	result += (1 - p) * cur / 3

	// 必勝法を使わずあいこになる
	result += recv((1 - p) * cur / 3, math.Min(1, p + q), q, turn + 1)
	return result
}

func main() {
	// ref http://yukicoder.me/submissions/118825
	sc := NewScanner()
	// 1回目で勝利する
	cur := 1.0 / 3
	fmt.Println(cur + recv(cur, float64(sc.NextInt()) / 100, float64(sc.NextInt()) / 100, 1))

}