Division doesn't always result in a mixed number. And you don't have a choice . . . either it does or it doesn't.
If you divide 12 by 3, it doesn't. You get just plain 4 with no fraction.
Dividing 12 by 3 results in 4, which is a whole number, not a mixed number. Therefore, it cannot be expressed as a mixed number. For a result that is a mixed number, consider dividing a number like 13 by 3, which gives 4 3 1 .
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