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# Statistics permutations/combinations question watch

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1. Please could you help me on this question, my mind has just gone completely blank.

A disc jockey has 12 tracks to play during an hour programme. He has unfortunately forgotten to bring the playlist giving the order of the tracks. He decides to play them in a random order, playing each track once.

What is the probability he plays the tracks in the correct order once.

Is the answer 12! and he has a 1 in 12! chance?
2. (Original post by 36CrazyfistsFay)
Please could you help me on this question, my mind has just gone completely blank.

A disc jockey has 12 tracks to play during an hour programme. He has unfortunately forgotten to bring the playlist giving the order of the tracks. He decides to play them in a random order, playing each track once.

What is the probability he plays the tracks in the correct order once.

Is the answer 12! and he has a 1 in 12! chance?
That's correct. You just need to state the probability rather than chances.

12 records. 12! possible orderings.

Since he only plays them once, probabilty of getting it correct is 1/12!

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