I have a permutation inquiry. While I mostly understand how to figure out the problem I've been given, from looking at the example, there's one number that I can't figure out where it came from so I don't know how to translate into my own problem.
Example given: Each student received a 4-digit code to use the library computers, with no
digit repeated. Manu received the code 7654. What was the probability that he would receive a code of consecutive numbers?

Question

I have a permutation inquiry. While I mostly understand how to figure out the problem I've been given, from looking at the example, there's one number that I can't figure out where it came from so I don't know how to translate into my own problem. 
Example given: Each student received a 4-digit code to use the library computers, with no
digit repeated. Manu received the code 7654. What was the probability that he would receive a code of consecutive numbers?

anonymous · Answer

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