A square sheet of paper is folded along the dotted lines in the direction of the arrows, and holes are then punched through all the layers, as shown in the figures. How will the sheet look when it is opened out?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) →
When a folded sheet is opened, every hole is repeated as its mirror image across each fold line, the last fold being opened first. Here first the top half is folded down onto the bottom half and then the left half is folded over onto the right half. Opening the second fold copies the 2 holes across the vertical fold line; opening the first fold then copies all of them across the horizontal fold line. So the opened sheet has 8 holes, placed symmetrically about the fold lines.
Option (2) — Incorrect. The copies across the vertical fold line (the second fold) are missing, so it shows only 4 holes.
Option (3) — Incorrect. It has an extra hole: the opened sheet has 8 holes, this option shows 9 holes.
Option (4) — Incorrect. Only the second fold has been opened: the copies across the horizontal fold line are missing, so it shows only 4 holes.