In a family, there are many children. Every boy in the family has as many brothers as the sisters. However, each girl has twice number of brothers as that of sisters.

Can you calculate the number of siblings in the given family ?

Suppose that the number of boys be "b" and number of girls be "g".

Now, each boy has equal number of brothers and sisters:
(b - 1) = g
=> (b - g) = 1 ------ (1)

In addition, each girl has twice as many brothers as sisters:
2 (g-1) = b
=> (2g - b) = 2 ------- (2)

From (1) and (2)
g = 3 and b = 4

Therefore, there are 4 boys and 3 girls in the family.

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