# Maths - probability

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#1

I don't get why the answer is A.
If a white counter is already taken then it leaves 1W+2B.
Therefore, the probability of getting a white on the second attempt is 1/3 since only 1 white out of 3?
Last edited by As.1997; 1 month ago
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1 month ago
#2
(Original post by As.1997)

I don't get why the answer is A.
If a white counter is already taken then it leaves 1W+2B.
Therefore, the probability of getting a white on the second attempt is 1/3 since only 1 white out of 3?
This might help: https://www.thestudentroom.co.uk/sho....php?t=5437900
1
1 month ago
#3
(Original post by As.1997)

I don't get why the answer is A.
If a white counter is already taken then it leaves 1W+2B.
Therefore, the probability of getting a white on the second attempt is 1/3 since only 1 white out of 3?
Heres a famous variant of the problem
https://en.wikipedia.org/wiki/Monty_...012%20%3D%2016.
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