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Problem
Alfred and four other people want to be in a group photograph. In how many different ways can they be arranged in a row with Alfred in the middle? (A) 4 (B) 8 (C) 12 (D) 24 (E) 40
Solution
The person on the extreme left can be any one of the four people that is not Alfred; the second left can be any one of the remaining three; the first person on the right of centre... and so on. The number of possibilities is .
Final answer
D
Techniques
Permutations