There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?
Common Wrong Answers
“On the floor in the center of the room”
If the apple is placed on the floor, all 20 people can see it, contradicting the requirement that only one person cannot see it.
“On a table in the corner of the room”
Placing the apple on a table would still allow everyone in the room to see it, as they are all facing the room and can see all corners.
“In the hands of one person”
If the apple is held by one person, that person would see it, thus failing to meet the condition that only one person cannot see it.
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