Question

A customer calls the customer service of the e-commerce site where he is shopping. Customer service cannot be reached as it is full 60% of the time. How likely is a customer who makes 7 calls in a row to be connected to customer service on any one call?

Answer 1

Binomial distribution: $P(X) = nCx p^x q^{n-x}$

Number of trials, n = 7

P(issue resolved in one hour), p = 0.60

$q = 1 - p = 0.40$

P( 7 calls in a row) = $P(7)$

$= 7C1*0.6^7*0.4^1$

= 7*0.01119744

=0.07838208