Question 16
To stick one sheet of paper on the whiteboard, Anna must use four magnets to fix the four corners. To stick two sheets on the whiteboard, she needs only six magnets, as shown. To stick 32 sheets of paper on the board, at least how many magnets does she need?
Editorial question note: use the illustrated convention of a complete, aligned rectangular grid of non-overlapping sheets, with magnets shared only at coincident corners. Find the minimum within that convention.
Editorial question note: use the illustrated convention of a complete, aligned rectangular grid of non-overlapping sheets, with magnets shared only at coincident corners. Find the minimum within that convention.