All four Kings from a deck of cards are placed face down on a table in a random order. You select two of them, and if both are the same color (red or black), then you win.
What’s your chance of winning?
There are two red and two black Kings on the table. The first card you select is irrelevant. If it is a black King, then of the remaining 3 cards, only one is black, and since your selection is random, you have a 1/3 chance of winning.
If the King you selected is red, there is only one red King left of the other three cards, and the same argument applies.
- Problem by Denton Young
- Solution by Denton Young
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