Question

A couple has 2 children. Find the probability that both are boys, if it is known that (1) one of the children is a boy; (2) the older child is a boy.

Answer 1

Answer:

2×1=2

2×2=4

one boy =2

second boy =4

Answer 2

Answer:

$(1) \dfrac{1}{4},\ \ (2)\ \dfrac{1}{2}$

Step-by-step explanation:

As given in the question,

total number of children = 2

probability of having one girl or one boy children will be 0.5.

we have to find the probability that both children are boy.

So, probability of having both boy,

$P(b=2)\ =\ \dfrac{1}{2}\times \dfrac{1}{2} =\ \dfrac{1}{4}$

So, probability of getting both boy children is $\dfrac{1}{4}$.

(1).probability of one of the children is a boy$=\ \dfrac{1}{2}\times \dfrac{1}{2}$

                                                                        $=\ \dfrac{1}{4}$

(2).probability of the older child is a boy= $\ \dfrac{1}{2}$