50 - 5 2/3 = 44 1/3
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It is hard to have 2/3 of a student (although many students seem to be only 2/3 there). Further, we are not told the mix of student is confined to the two grades. If the non-sixth-graders are all 7th graders, then the answer is 0.
_____
It is hard to have 2/3 of a student (although many students seem to be only 2/3 there). Further, we are not told the mix of student is confined to the two grades. If the non-sixth-graders are all 7th graders, then the answer is 0.