import sequtils,strutils
var
    P,Q : int
    A = stdin.readline.split.map(parseInt)
(P, Q) = A
if P == 0:
    echo 0
else:
    var
        p = P.float64 / 100
        q = Q.float64 / 100
    echo(p * q / ((1.0 - p) * (1.0 - q) + p * q) * 100)