There are 8 boys and 4 girls giving interview for a job. If three of them are selected, then what is the probability that one of the three is a girl and the other two are the boys?

Total Number of candidates = 12 Let ‘S’ be the Sample Space Then, n(S) = number of ways of three candidates who got selected n(S) = ^{12}C3 = 220 Let ‘E’ be the event of 1 girl and 2 boys selected Therefore, n(E) = number of possibility of 1 girl out of 4 and 2 boys out of 8 n(E) = ^{4}C1 × ^{8}C2 = 4 × 28 = 112 Now the required Probability = 112/220 = 28/55

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