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Posers and Puzzles

Posers and Puzzles

  1. 15 Jul '04 20:03 / 1 edit
    Did someone change the lock to this forum's door???

    Here is one:

    Census Taker: How many children do you have?
    Woman: Two.
    Census Taker: And their ages?
    Woman: One is five, one is two.
    Census Taker: Is one of them a girl?
    Woman: Yes.

    What is the probability that her other child is a girl?
    (Assume every pregnancy has a 50/50 chance to be a boy or a girl.)

    Show your work.

  2. Standard member Nemesio
    15 Jul '04 21:48
    1/3 chance of the other being a girl.

    Since we know one is a girl, the combinations could be:

    GG, GB, BG.

  3. 15 Jul '04 21:52
    Good work.

  4. Donation richjohnson
    15 Jul '04 22:15
    Keeping with your 50/50 assumption, what is the probability that a woman who is pregnant for her second time, and who has previously given birth to a girl, will give birth to another girl?
  5. Standard member royalchicken
    16 Jul '04 04:30
    Please refer to the numerous Monty Hall Problem threads.