A Bank Offers Online Banking to Its Customers Free of Charge

Essay

A bank offers online banking to its customers free of charge. While online, customers can also sign up for additional services that the bank offers. Let $x$ be the number of customers who sign up for additional services online each day. Suppose the distribution of $x$ is approximated well by a Poisson distribution with mean $\lambda = 42.3$ . Find $E ( x )$ and interpret its value.