#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <stack>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

double ret;
double p0, q;

void rec(double p, bool prev, double x, int depth, bool first = false){
  if(depth>25) return;
  //win
  if(prev) ret += x * (1/2.0);
  else ret += x * (1/3.0);
  //draw
  if(prev){
    double t = p-q;
    if(t<0.0) t = 0.0;
    rec(t, true, (1/2.0) * t * x, depth+1);
    rec(t, false, (1/2.0) * (1-t) * x, depth+1);
  }else{
    if(first){
      rec(p0, true, (1/3.0) * p0 * x, depth+1);
      rec(p0, false, (1/3.0) * (1-p0) * x, depth+1);
    }else{
      double t = p+q;
      if(t>1.0) t = 1.0;
      rec(t, true, (1/3.0) * t * x, depth+1);
      rec(t, false, (1/3.0) * (1-t) * x, depth+1);
    }
  }
}

int main(){

  int p0int, qint;
  cin >> p0int >> qint;
  p0 = p0int/100.0;
  q = qint/100.0;

  ret = 0;
  rec(0, false, 1.0, 0, true);

  printf("%.10lf\n", ret);
  
  return 0;
}