Thread: probability question

If we say there are 3 boy and 6 girls lined up in random order (all permutations are equal) and were asked to determine the probability that the 2nd is a boy, would the answer to that question be the same if we had 3 red balls and 6 blue balls that are drawn in succession and were replaced? and would the answer be the same whether we ask for the probability of the 3rd 4th and so on... that it is a boy?

So, 3 boys, 6 girls. There are a total of nine children, one-third are boys. The probability that the second child is a boy is 1/3. And it would be that probability, except it would be the same even if they weren't replaced. After your first pick, you can change the probability up or down. But before that, it is 1/3.

you're saying that if we had 3 red balls and 6 blue balls that are drawn in succession, but are not replaced it would still be the same for any cases?

Originally Posted by EdmureTully

you're saying that if we had 3 red balls and 6 blue balls that are drawn in succession, but are not replaced it would still be the same for any cases?

Yes. As long as have no information about the balls already chosen.

Ok thanks

The probability of an event is equal to the number of favorable outcomes over the number of possible outcomes. The boy and girl case is the same.

thanks