A drawer contains 36 stocks and 2 stocks are selected at random without replacement. What is the probability that both socks are black?
1.The probability is 4/9 that the first sock is black.
2.The number of white socks in the drawer is 4 more than the number of black socks.
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Laura GMAT Tutor
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Ask yourself what you need to know in order to answer the question: how many of the 36 socks are black?danjuma wrote:A drawer contains 36 stocks and 2 stocks are selected at random without replacement. What is the probability that both socks are black?
1.The probability is 4/9 that the first sock is black.
2.The number of white socks in the drawer is 4 more than the number of black socks.
(1) tells us that 4/9 of the 36 socks are black. SUFF
(2) tells us that there are at least 4 black socks. However, there may be socks that are neither black nor white NOT SUFF
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