There are 8 magazines lying on a table; 4 are fashion magazines and the other 4 are sports magazines. If 3 magazines are to be selected at random from the 8 magazines, what is the probability that at least one of the fashion magazines will be selected?
~$\frac{1}{2}$~
~$\frac{2}{3}$~
~$\frac{32}{35}$~
~$\frac{11}{12}$~
~$\frac{13}{14}$~
1. 共有56种情况,C(3,8),其中全是sports的有4种,C(3,4), at least有52种,52/56 = 13/14
2. (4*3*2 )/ (8*7*6)= 1/14, 1 - 1/14 = 13/14
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