Answer to Question #153000 in Statistics and Probability for Benjamin

Question

An experiment involves studying the composition of genders of a set of triplets What is the probability that there are 2 boys and a girl in the set?

a. 0.875
b. 0.125
c. 0.375
d. 0.625

Answer 1

Let's denote G for the birth of the girl and B for the birth of the boy.

There 8 possible outcomes:

BBB, BBG, BGB, GBB, BGG, GBG, GGB, GGG.

There are 2 boys and a girl: BBG, BGB, GBB.

Therefore the probability that there are 2 boys and a girl in the set is $\frac{3}{8}=0.375$

Answer: c 0.375.