Counting and Probability

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You need to arrange your 3 friends and you (Tom, Peter, Bob and George) in the bistro queue, in a single-file line. However, Tom and Bob are best friends, so you have to put them next to each other, or they won't even come into the queue. How many ways can you arrange yourselves?

Comments

  1. Anonymous29 September 2020 at 07:25

    Let us say Tom and Bob are just one person, because they have to stand next to each other. This means we have 3 people so 3! is six. but we have to double this as Tom and Bob can be swapped around so the end answer is 12

    ReplyDelete

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