In a binomial distribution the occurrence and the non-occurrence of...

In Binomial distribution, if $p$ is the probability of certain event to happen and $q$ is the probability of its failure in a single trial then $p+q=1$. Here given $p=q$ (As both events are equally likely) so, $p=\frac{1}{2}$ Now, mean $\mu=($ Number of trials $) \times p$$\begin{aligned}& & 6 & =n \cdot \frac{1}{2}\end{aligned}$$$or,$n=12$