Hello,
I cam across this question while studying:
A bag contains 6 black chips numbered 1-6 respectively and 6 white chips numbered 1-6 respectively. if pavel reaches into the bag of 12 chips and removes 2 chips, one after the other, without replacing them, what is the probability that he will pick black chip #3 and then white chip #3?
I got 11!/12! = 1/12
My answer is wrong but it answers a different question (what is the probability that he will pick W3 immediately after B3?)
When I read the question, I immediately thought that the question was asking about the probability that he will pick black chip #3 and then white chip #3, not “what’s the probability he picks B3 first and W3 second”.
What should I pay attention to in the future to avoid this mistake in interpretation?