The couple has two children and one is known to be boy,
The probability that the other is boy will be $=$
$\frac{Favourable-outcome}{Total-outcome}$
Total outcomes are 3 ,
The first child is a boy, the second girl
The first child is a girl, the second boy
The first child is a boy, second boy
The favourable outcome is one,
Thus, the probability that the other is boy will be
$\Rightarrow 1 / 3$
Hence, the correct option is a.
A couple has 2 children. What is the probability that both are boys. If it is known that one of them is a boy?
A. $\frac{1}{3}$
B. $\frac{2}{3}$
C. $\frac{3}{4}$
D. $\frac{1}{4}$
A. $\frac{1}{3}$
B. $\frac{2}{3}$
C. $\frac{3}{4}$
D. $\frac{1}{4}$
A couple has 2 children. What is the probability that both are boys. If it is known that one of them is a boy?
A. $\frac{1}{3}$
B. $\frac{2}{3}$
C. $\frac{3}{4}$
D. $\frac{1}{4}$
A. $\frac{1}{3}$
B. $\frac{2}{3}$
C. $\frac{3}{4}$
D. $\frac{1}{4}$