A coin is tossed three times. Let $X$ denote the number of times a tail follows a head. If $\mu$ and…
- $51$
- $64$
- $32$
- $48$
Solution

$\begin{aligned} & \mu=\sum x_i P_i=\frac{1}{2} \\ & \sigma^2=\sum x_i^2 P_i-\mu^2 \\ & =\frac{1}{2}-\frac{1}{4}=\frac{1}{4} \\ & 64\left(\mu+\sigma^2\right)=64\left[\frac{1}{2}+\frac{1}{4}\right] \\ & =64 \times \frac{3}{4}=48\end{aligned}$ ~
Asked in: JEE Main 2025 (22 Jan Shift 1)