Solution #38: Product

3024 ends in neither a 5 nor a 0; therefore, none of the four numbers given can be divisible by 5 or by 10. If all four numbers were greater than 10, their product would exceed 10,000, which is not the case. The four numbers must either be {1,2,3,4} or {6,7,8,9}. In the first case, the product is 24. The answer can only be {6,7,8,9}, as can be easily verified.
Source: Berrondom, Marie
Categories: Arithmetic, Multiplication
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