Question 863750
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Hi
21 students: 12F, 9S
 5 students are selected at random
P(2F)  = {{{(12C2)(9C3)/(21C5)}}}
P(at least one S) = {{{(21C5 - 12C5)/(21C5)}}} = 1 - 12C5/21C5   (1-P(5F))