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The multiplication in the first box could have gone something like this: 2 x 28, 2 x 12, 2 x 56 and 2 x 108, or 4 x 14 , 4 x 6,4 x 28 and 4 x 54, or 8 x 7, 8 x 3, 8 x 14 and 8 x 27. Therefore, 8 would be the biggest multiplication that could go on in the box.