Challenge Intuition Inspiration (Volume 1 and 2)

Author: Yaxiao Si, Konoeda Hiroshi
Translator: Ding Jianmin
Publisher:
Publish Date: 2004-09-01
Features:
Q: There are three types of beings: angels, demons, and humans. Angels always tell the truth, demons always lie, and humans sometimes tell the truth and sometimes lie. A woman in a black dress says, "I am not an angel." A woman in a blue dress says, "I am not a human." A woman in a white dress says, "I am not a demon." So, who are they?
Q: A woman gives 100 yuan to a man, and they end up with the same amount of money. When the man gives 100 yuan to the woman, the woman has twice as much money as the man. How much money did each person originally have? Solving this problem doesn't require an equation. If you have a bit of mathematical intuition, the answer comes easily.