#include <bits/stdc++.h>
using namespace std;

#define DUMP(x) cerr << #x << "=" << x << endl
#define DUMP2(x, y) cerr<<"("<<#x<<", "<<#y<<") = ("<<x<<", "<<y<<")"<< endl
#define BINARY(x) static_cast<bitset<16> >(x)

#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define REP(i,m,n) for (int i=m;i<(int)(n);i++)

#define in_range(x, y, w, h) (0<=(int)(x) && (int)(x)<(int)(w) && 0<=(int)(y) && (int)(y)<(int)(h))
#define ALL(a) (a).begin(),(a).end()

typedef long long ll;
const int INF   = 1e9;
const ll  INFLL = 1e18;
typedef pair<int, int> PII;
int dx[4]={0, -1, 1, 0}, dy[4]={-1, 0, 0, 1};

double p0, q;

double dfs(int n, double p)
{
    double res = 0.0;
    if (n == 20) return res;

    res += 0.5 * p; // win
    res += 1 / 3.0 * (1.0 - p); // win

    res += 0.5 * p * dfs(n + 1, max(0.0, p - q)); //draw
    res += 1 / 3.0 * (1.0 - p) * dfs(n + 1, min(1.0, p + q)); //draw

    return res;
}

int main()
{
    ios::sync_with_stdio(false);
    
    cin >> p0 >> q;
    p0 /= 100, q /= 100;

    cout << fixed << setprecision(10);
    cout << 1/3.0 * (1.0 + dfs(1, p0)) << endl;
}