A man has four chairs. He breaks one and throws it away. The question does not ask how many usable chairs remain; it asks how many chairs does he still own?
Answer: 4 chairs.
Breaking a chair does not automatically change its ownership, and neither does physically throwing it away. The wording is the trick. He began as the owner of all four chairs, including the broken one. Unless the riddle says that ownership was transferred to somebody else, he can still be considered the owner of all four.
Many people immediately answer three because they focus on the chair that was discarded. The word “own” is what changes this from simple subtraction into a trick question.


