Question

How would you solve this question?

Let X represent the number of times a customer uses a particular service during a calendar month. Past data shows the following probability distribution for X 0 1 2 3 5 X РX-x) 0.5 0.2 0.1 0.1 0.1 What is the expected number of times a customer uses the service in a month if they use it at least once? Select one or more: а. 1 b. 2.4 с. 1.6 d. 0.5 е. 1.2

Answer 1

Here the question says us they use it atleast once in a month so atleast once means once or more than once . It doesn't include the zero values so we can find the expected value by avoiding the zero ,

$E(X) =\sum_{x=1,2,3,5} x P(x)$

= (1×0.2) + (2×0.1) + (3×0.1) + (5×0.1)

= 0.2 + 0.2 + 0.3 + 0.5

= 1.2

So the answer is

● e) 1.2