Question

HR calls 15 software and 10 marketing professionals for an interview. Three persons are selected from them. The probability that 2 software and 1 marketing personnel are selected from them is:
A. 3/25
B. 1/50
C. 25/117
D. 21/46

Answer 1

The probability that 2 software personnel are selected is (15/25)*(14/25)

The probability that 2 software and 1 marketing personnel are selected is (15/25)*(14/24)*(10/23)*3

= 21/46.

Hope this helps.

Answer 2

Number of software professionals = 15

Number of marketing professionals = 10

Total number of professionals = 25

Find the number of permutations for 2 software professionals and one marketing professional :

Number of unique permutations = 3!/2! = (3 x 2 x 1) / (2 x 1) = 3

Find the probability of choosing 2 software professionals and 1 marketing professional:

P(2 software and 1 marketing) =  3 x (15/25)(14/24)(10/23) = 21/46

Answer:(D) 21/46