Find the 6-digit number beginning and ending in the digit 2 that is the product of three consecutive even integers.
HMMT February
Solution
Because the last digit of the product is 2, none of the three consecutive even integers end in 0. Thus they must end in or , so they must end in since does not end in 2. Call the middle integer . Then the product is , so , but clearly . Thus , and the product is .
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