The probability mass function of random variable X is given by
$$P[X=r]=\left\{\begin{array}{ll}
\frac{{ }^n C_r}{32}, & n, r \in \mathbb{N} \\
0, & \text { otherwise }
\end{array} \text {, then } P[X \leq 2]=\right.$$
Three fair coins numbered 1 and 0 are tossed simultaneously. Then variance Var (X) of the probability distribution of random variable $$\mathrm{X}$$, where $$\mathrm{X}$$ is the sum of numbers on the uppermost faces, is
an urn contains 9 balls of which 3 are red, 4 are blue and 2 are green. Three balls are drawn at random from the urn. The probability that the three balls have difference colours is
It is observed that $$25 \%$$ of the cases related to child labour reported to the police station are solved. If 6 new cases are reported, then the probability that at least 5 of them will be solved is