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    An examination paper consists of 8 questions, of which one is on geometric distributions and one is on binomial distributions.
    Four of the questions, including the one on geometric distributions, are worth 7 marks each, and the remaining four questions, including the one on binomial distributions, are worth 9 marks each. The 7-mark questions are the first four questions on the paper, but are arranged in random order. The 9-mark questions are the last four questions, but are arranged in random order. Find the probability that
    the questions on geometric distributions and on binomial distributions are next to one another,

    The answer according to the mark scheme is 1/16 but how exactly do you get to that?
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    (Original post by Chelsea12345)
    An examination paper consists of 8 questions, of which one is on geometric distributions and one is on binomial distributions.
    Four of the questions, including the one on geometric distributions, are worth 7 marks each, and the remaining four questions, including the one on binomial distributions, are worth 9 marks each. The 7-mark questions are the first four questions on the paper, but are arranged in random order. The 9-mark questions are the last four questions, but are arranged in random order. Find the probability that
    the questions on geometric distributions and on binomial distributions are next to one another,

    The answer according to the mark scheme is 1/16 but how exactly do you get to that?
    The only way they can be next to each other is if the Geo distr. question is 4th and the Bino distr. question is 5th. What is the probability that, in their respective sets of 4, they take these places? These are two separate events, so work out the probability they happen at the same time.
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    (Original post by RDKGames)
    The only way they can be next to each other is if the Geo distr. question is 4th and the Bino distr. question is 5th. What is the probability that, in their respective sets of 4, they take these places? These are two separate events, so work out the probability they happen at the same time.
    I understood the bit about the geo question being 4th and binomial question being 5th.
    So to work out these as a separate events,
    do i just 3! * 4!?
    I know we have to group two things together and count as them as one when working out the arrangements but i think i'm confused by the fact that there two separate questions if that makes sense?
 
 
 
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