Since for a boy he has an equal number of brothers and sisters the number of boys is x+1 while there are x girls
The number of sisters for a girl is equal to half the number of boys so the number of boys is y and the number of girls is (y/2)+1.
[tex](x+1)+x=y+ \frac{y}{2} +1 \\ 2x= \frac{3y}{2} \\ x= \frac{3y}{4} [/tex]
The LHS is the total number of children for the boy and the RHS is the total number of children for the girl.
We substitute the value of x to y
[tex] \frac{3y}{4} +1=y \\ 3y+4=4y \\ 4=y[/tex]
Since the number of boys is 4 the number of girls is [tex] \frac{4}{2} +1=2+1=3[/tex].
