#include <algorithm>
#include <complex>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <vector>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define rrep(i, n) for (int i = (n)-1; i >= 0; i--)
using namespace std;
typedef long long int lli;
typedef pair<lli, lli> P;
lli MOD = 1000000007;
double f(double, int);
double g(double, int);
double p, q;
double r = 1.0 / 3.0;
double fdp[105] = {};
double gdp[105] = {};
double f(double x, int dph)
{
    int xx = (int)(x * 100);
    //if (fdp[xx] != 0)
    //return fdp[xx];
    double tp = min(1.0, x + q);
    if (dph == 0)
        return 0;
    return fdp[xx] = tp * 0.5 + tp * 0.5 * g(tp, dph - 1) + (1 - tp) * r + (1 - tp) * r * f(tp, dph - 1);
}
double g(double x, int dph)
{
    int xx = (int)(x * 100);
    //if (gdp[xx] != 0)
    //return gdp[xx];

    double tp = max(0.0, x - q);
    if (dph == 0)
        return 0;
    return gdp[xx] = tp * 0.5 + tp * 0.5 * g(tp, dph - 1) + (1 - tp) * r + (1 - tp) * r * f(tp, dph - 1);
}

int main()
{
    cin >> p >> q;
    p /= 100.0;
    q /= 100.0;
    double ans = 0;
    ans = r + r * (p * 0.5 + p * 0.5 * g(p, 20) + (1 - p) * r + (1 - p) * r * f(p, 20));
    printf("%.10f\n", ans);
}