Solutions - 5190-06

(1) Find the marginal PMF of $X$ by summing rows:

$k$	0	1	2
$P_X(k)$	.25	.5	.25

---

(2) Compute $E[X]$:

$$\begin{array}{c}E[X]=0(0.25)+1(0.5)+2(0.25)\gg \gg 1\end{array}$$