Two different families A and B are bles | vedclass

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Question

Let the number of children ineach familybe $x$.

Thus the total number of children in both the families are $2 x$

Now, it is given that $3$ ticke

Vedclass · Accepted Answer

$5$

Vedclass · Answer

Let the number of children ineach familybe $x$.

Thus the total number of children in both the families are $2 x$

Now, it is given that $3$ tickets are distributed amongst the children of these two families.

Thus, the probability that all the three tickets go to the children in family $B$

$=\frac{^{x} C_{3}}{^{2 x} C_{3}}=\frac{1}{12}$

$\Rightarrow \frac{x(x-1)(x-2)}{2 x(2 x-1)(2 x-2)}=\frac{1}{12}$

$\Rightarrow \frac{(x-2)}{(2 x-1)}=\frac{1}{6}$

$\Rightarrow x=5$

Thus, the number of children in each family is $5$.

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