use std::collections::VecDeque;


fn main() {
    let mut pq = String::new();
    std::io::stdin().read_line(&mut pq).ok();
    let pq: Vec<usize> = pq.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let p0 = pq[0] as f64 / 100.;
    let q = pq[1] as f64 / 100.;

    let mut deque = VecDeque::new();
    let mut result = 1. / 3.;
    deque.push_back((1. / 3., 0, p0));
    while let Some((prob, pattern, pprev)) = deque.pop_front() {
        if prob < 1e-12 { continue; }
        let p = if pattern == 0 { pprev } else if pattern == 1 { pprev - q } else { pprev + q };
        let p = p.max(0.).min(1.);
        let used_pattern = prob * p / 2.;
        let unused_pattern = prob * (1. - p) / 3.;
        result += used_pattern;
        result += unused_pattern;
        deque.push_back((used_pattern, 1, p));
        deque.push_back((unused_pattern, 2, p));
    }
    println!("{}", result);
}