N = int(input())
r = float(input())
p = float(input())
a = 1 - p - r
r0 = 0
p0 = 1
a0 = 0
if r != 1:
    for _ in range(N):
        r0,p0 = r0 + p0*p0*r/(1-r*r0),p*p0/(1 - r*r0)
    print(r0)
else:
    print(1)