import sys
N=int(input())
q=float(input())
p=float(input())
if N==1:
    print(q)
    sys.exit()
dp=[0.0]*N
dp1=[0.0]*N
dp[0]=1
ans=0
for k in range(1000):
    ndp=[0.0]*N
    ndp1=[0.0]*N
    for i in range(1,N):
        ndp[i]=p*dp[i-1]+q*dp1[i]
    ndp1[N-1]=q*dp[N-1]
    for i in range(N-2,-1,-1):
        ndp1[i]=p*dp1[i+1]+q*dp[i]
    dp=ndp
    dp1=ndp1
    ans+=dp1[0]
print(ans)