Question

It is given that a family of 2 children has a girl, what is the probability that the other child
also a girl?
(a) 0.50
(b) 0.25
(c) 1/3
(d) 2/3​

Answer 1

Answer:

(c) 1/3

Step-by-step explanation:

let A be the event that any one child is girl.

and B is the event that both are girls.

now,

sample space= {bb, bg, gb, gg}

n(A)= {bg, gb, gg}

n(B)= {gg}

p(A)= 3/4

p(B)= 1/4

n(A∩B)= {gg}

p(A∩B)= 1/4

now, probability of having a girl given that the other child is already a girl =

p(B/A)= p(A∩B)/p(A)

= (1/4)/(3/4)

= 1/3