Believe its 3 sorry if its wrong
Its eeither transposing or trabsposition
Hi! You need 3 boxes because if you divide 21 1/4 / 10 you get 2 1/8 or 2.125 so you at least have two boxes. You will still have some left over after the two boxes so you will need another box for those. I hope this helped, Goodluck :)
Answer:
Help with what?
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