Probability That Both Children Are Girls

Walking down the street one day, I met a woman strolling with her daughter. “What a lovely child,” I remarked. “In fact, I have a younger child as well,” she replied.

What is the probability that both of her children are girls?

1/2 probability. This has been know to cause raging debates and is known as one of the variations of the Boy or Girl paradox. This variation is more straightforward because knowing the position of the child leaves only two possibilities – the other child is a boy or a girl, each of which have a 1/2 probability.

Another variation of this can be found here.

Posted in Brain Teasers


1 Comment on "Probability That Both Children Are Girls"

At Least One is a Boy | Riddles and Brain Teasers says
November 5, 2013 @ 16:56

[…] This is a well-known problem known as the Boy or Girl paradox. The other variation is this brain teaser. […]

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