



 
Christine, Preliminary idea
Probability that AT LEAST ONE got an A So, let's work on the probability that none got an A Because there is one less person, and this person didn't get an A: On the second selection, there are 11 out of 14 ways to select a person who did not get an A. Thus, the probability that none got an A = (12/15) x (11/14) = (12x11)/(15x14) = 132/210 = 22/35 The number of ways to select 2 people from the 12 people who did not get an A The probability that none got an A = 66/105 = 22/35 Hence,
probability that AT LEAST ONE got an A = 1  22/35 = 13/35 (approximately 37%).  


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