Question 1200754
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<pre>

The opposite (the complementary) event is "no one of two children is a boy",
i.e. both children are girl.

For this complementary event, the probability is  {{{(1/2)*(1/2)}}} = {{{1/4}}}.

Hence, for the original event under the problem's question the probability is  {{{1 - 1/4}}} = {{{3/4}}}.    <U>ANSWER</U>
</pre>

Solved.



You can come to the same answer by writing and counting the events in the space of events

<pre>
    Girl Girl
    Boy  Girl
    Girl Boy
    Boy  Boy


In this table, all possible configurations are listed, and they all are equally likely.

The configurations that satisfy the problem, are ## 2, 3 and 4  of the table, 
giving the answer regarding the probability.
</pre>

Solved and fully explained in two ways, for your better understanding.