<h3>
Answer: 8</h3>
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Work Shown:
Let's say there are 28 cards in a full stack.
6/7 = 24/28 after multiplying top and bottom by 4
Since he has 24/28 of a stack left, this means he has 24 cards left.
He wants to arrange the remaining cards into piles so that each pile consists of 3/28 of a full stack. In other words, he wants each pile to have 3 cards.
So this must mean he will get 24/3 = 8 piles
(8 piles)*(3 cards per pile) = 8*3 = 24 cards total