Let $x$ represent the number of times a customer visits a grocery store in a 1 -week period. Assume this is the probability distribution of $x$ :
$$\begin{array}{l|cccc}x & 0 & 1 & 2 & 3 \\\hline p(x) & .1 & .4 & .4 & .1\end{array}$$
Find the expected value of $x$, the average number of times a customer visits the store.