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Question
There are 6 items in column A and 6 items in column B. A student is asked to match each item in column A with an item in column B. How many possible, correct or incorrect, answers are there to this question?
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Solution
Each answer is an arrangement of the 6 items of column B keeping the order of column A fixed.
∴ Total number of answers = Number of arrangements of items in column B = 6P6 = 6! = 720
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