Answer:
D. p ≤ 24
Explanation:
The area of a piece of paper is 8.5·11 = 93.5 square inches, so the area of the bulletin board is that of ...
1728/93.5 ≈ 18.48
pieces of paper.
The solution is a number greater than 18, so selection D is the only viable choice.
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The bulletin board is 24 inches high and 1728/24 = 72 inches wide. If Mrs. Wickowitz hangs the papers "sideways", then 3 of them will cover 25.5 inches vertically, and 7 of them will cover 77 inches horizontally. That's 3·7 = 21 whole sheets of paper. That, too, matches selection D.