Required Mathematical Intelligence

Chapter 97 Colorful Socks
There are 10 red socks and 10 blue socks scattered in a closet drawer.These 20 socks are all the same except for different colors.Now the room is dark, and you want to take two socks of the same color from the drawer.What is the minimum number of socks that must be removed from the drawer to ensure that two of them make a pair of the same color?
[Answer: Many people who try to solve this puzzle say to themselves, "Suppose the first sock I pull out is a red sock. I need to pull out another red sock to match it, but the second sock I pull out may It is a blue sock, and the next one, and the next one, and so on, may be blue socks, until all 10 blue socks in the drawer are taken out. Therefore, the next one must be a red sock. Therefore, the answer Must be 12 socks."

However, this reasoning ignores something.There is no limit to a pair of red socks in the title, it only requires to take out two socks of the same color so that they can be paired.If the first two socks removed do not match, then the third must match one of the first two socks.So the correct answer is 3 socks. ]
(End of this chapter)