He has only six socks in his drawer, a mixture of black and white. If he chooses two socks, the chances that he draws out a white pair is 2/3. What are the chances that he draws out a black pair?
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He has a ZERO chance of drawing out a black pair.
Since there is a 2/3 chance of drawing a white pair, then there MUST be 5 white socks and only 1 black sock. The chances of drawing two whites would thus be: 5/6 x 4/5 = 2/3 . With only 1 black sock, there is no chance of drawing a black pair.
Since there is a 2/3 chance of drawing a white pair, then there MUST be 5 white socks and only 1 black sock. The chances of drawing two whites would thus be: 5/6 x 4/5 = 2/3 . With only 1 black sock, there is no chance of drawing a black pair.
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if there is a 2/3 chance, thats also a 4/6 chance meaning there are 4 white socks and 2 black socks. so 2/6 is 1/3 chance for a black socks while theyre all still there. the first black sock has a 1/3 chance, but then there is only one black sock left and 5 socks in the drawer, so its 1/5. multiply them together, 1/3*1/5 and its 1/15