output_description: Print the expected number of games that will be played, in the manner
  specified in the statement.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N A B C
attempt: #!/usr/bin/env python
  
  import sys
  
  MOD = 10**9 + 7
  
  
  def Add(n, m):
      return (n + m) % MOD
  
  
  def Sub(n, m):
      return (n - m) % MOD
  
  
  def Mul(n, m):
      return (n * m) % MOD
  
  
  def Pow(n, p):
      if p < 0:
          return Pow(n, (p % (MOD - 1)))
      elif p == 0:
          return 1
      elif p == 1:
          return n
      elif p % 2 == 0:
          tmp = Pow(n, (p // 2)) % MOD
          return tmp**2 % MOD
      else:
          tmp = Pow(n, (p // 2)) % MOD
          return (n * tmp**2) % MOD
      #
      raise ValueError
  
  
  def Div(n, m):
      return (n * Pow(m, MOD - 2)) % MOD
  
  
  #
  #::::::::::::::::::::::::::::::::::::::::::::::::::
  n, a, b, c = [int(x) for x in sys.stdin.readline().split()]
  #
  h = Div(1, 100)
  pa = Mul(a, h)
  pb = Mul(b, h)
  cc = Div(1, Mul(100 - c, h))
  # power of n
  cn = Pow(cc, n + 1)
  t = Mul(cn, n)
  an = Mul(Pow(pa, n), t)
  bn = Mul(Pow(pb, n), t)
  # for A
  pam = bn
  pac = Mul(pa, cc)
  # for B
  pbm = an
  pbc = Mul(pb, cc)
  # permutation
  mbar = n
  perm = [1] * n
  for m in range(1, n):
      mbar -= 1
      perm[m] = Mul(perm[m - 1], mbar)
  perm.reverse()
  nfact = perm[0]
  #
  ret = 0
  ncm = 1
  for m in range(n):
      if m > 0:
          ncm = Mul(ncm, n + m)
          pam = Mul(pam, pac)
          pbm = Mul(pbm, pbc)
      #
      ret = (ret + Mul(Mul(ncm, pbm + pam), perm[m])) % MOD
  #
  print(Div(ret, nfact))
  
problem_description: Statement
  
  Takahashi and Aoki will play a game. They will repeatedly play it until one of
  them have N wins in total.
  
  When they play the game once, Takahashi wins with probability A %, Aoki wins
  with probability B %, and the game ends in a draw (that is, nobody wins) with
  probability C %. Find the expected number of games that will be played, and
  print it as follows.
  
  We can represent the expected value as P/Q with coprime integers P and Q.
  Print the integer R between 0 and 10^9+6 (inclusive) such that R \times Q
  \equiv P\pmod {10^9+7}. (Such an integer R always uniquely exists under the
  constraints of this problem.)
samples: [{"input": "1 25 25 50", "output": "2\n    \n\nSince N=1, they will repeat the game until one of them wins. The expected\nnumber of games played is 2.\n\n* * *"}, {"input": "4 50 50 0", "output": "312500008\n    \n\nC may be 0.\n\n* * *"}, {"input": "1 100 0 0", "output": "1\n    \n\nB may also be 0.\n\n* * *"}, {"input": "100000 31 41 28", "output": "104136146"}]