The probability is 1⁄5 (as independently calculated by me). I’ve no idea if argument 2 is correct, because I don’t understand it. My reasoning:
There are 6 combinations of 2 cards: AsAh, As2c, As2d, Ah2c, Ah2d, 2c2d.
Of these, only the first 3 (AsAh, As2c, As2d) could I have answered yes to both questions (assuming I’m not lying, wihch is outside the context).
But if I have AsAh, only 1⁄2 the time would I have answered yes to the second question. So AsAh needs 1⁄2 the weight of the other 2 possibilities.
So the probability is (1/2)/(2+1/2) = 1⁄5.
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The probability is 1⁄5 (as independently calculated by me). I’ve no idea if argument 2 is correct, because I don’t understand it. My reasoning:
There are 6 combinations of 2 cards: AsAh, As2c, As2d, Ah2c, Ah2d, 2c2d.
Of these, only the first 3 (AsAh, As2c, As2d) could I have answered yes to both questions (assuming I’m not lying, wihch is outside the context).
But if I have AsAh, only 1⁄2 the time would I have answered yes to the second question. So AsAh needs 1⁄2 the weight of the other 2 possibilities.
So the probability is (1/2)/(2+1/2) = 1⁄5.