tronella: (Default)
So. Most people got the right answer in the second question of my maths quiz yesterday, but... everyone is arguing with me about the first one.

Q: A couple has two children, one of whom is a girl. What is the probability that the other one is a girl?
A: 1/3

Answers from other people:
[livejournal.com profile] trollprincess -- 50/50
[livejournal.com profile] louiselux -- a 50/50 chance?
[livejournal.com profile] crossbow1 -- 50/50
[livejournal.com profile] omylouse -- 0.5
[livejournal.com profile] debauchingbeast -- half?
[livejournal.com profile] slicesmissus -- 1 in 2?
[livejournal.com profile] eor -- Approximately 1 in 2.
[livejournal.com profile] enigma_o -- 50% or 0% depending on how you take 'one of whom'
[livejournal.com profile] letting_it_out -- Fifty-fifty
[livejournal.com profile] mollydot -- 50%
[livejournal.com profile] invisigoth51 -- 50%

Everyone disagrees with me! And people are still arguing with me in the comments of that post, so I assume I am not explaining myself well. So, some links for you!

Wikipedia: Boy or Girl paradox. (Pf, it is not really a paradox.) The question I asked corresponds to the second question on that page: they ask "A random two-child family with at least one boy is chosen. What is the probability that it has a girl?", so their answer is 1 - my answer.

Ask Dr Math: a forum thread of some people talking about this question (but with two boys instead of two girls).

Cut The Knot has two examples: one where for some reason they have bears instead of children, and one using black and white counters.

I hope these are useful in understanding the problem! :)
tronella: (Default)
So. Most people got the right answer in the second question of my maths quiz yesterday, but... everyone is arguing with me about the first one.

Q: A couple has two children, one of whom is a girl. What is the probability that the other one is a girl?
A: 1/3

Answers from other people:
[livejournal.com profile] trollprincess -- 50/50
[livejournal.com profile] louiselux -- a 50/50 chance?
[livejournal.com profile] crossbow1 -- 50/50
[livejournal.com profile] omylouse -- 0.5
[livejournal.com profile] debauchingbeast -- half?
[livejournal.com profile] slicesmissus -- 1 in 2?
[livejournal.com profile] eor -- Approximately 1 in 2.
[livejournal.com profile] enigma_o -- 50% or 0% depending on how you take 'one of whom'
[livejournal.com profile] letting_it_out -- Fifty-fifty
[livejournal.com profile] mollydot -- 50%
[livejournal.com profile] invisigoth51 -- 50%

Everyone disagrees with me! And people are still arguing with me in the comments of that post, so I assume I am not explaining myself well. So, some links for you!

Wikipedia: Boy or Girl paradox. (Pf, it is not really a paradox.) The question I asked corresponds to the second question on that page: they ask "A random two-child family with at least one boy is chosen. What is the probability that it has a girl?", so their answer is 1 - my answer.

Ask Dr Math: a forum thread of some people talking about this question (but with two boys instead of two girls).

Cut The Knot has two examples: one where for some reason they have bears instead of children, and one using black and white counters.

I hope these are useful in understanding the problem! :)

November 2016

S M T W T F S
  12345
6789101112
1314151617 1819
20212223242526
27282930   

Syndicate

RSS Atom

Most Popular Tags

Style Credit

Expand Cut Tags

No cut tags