Question $3$:

A single automated checkout machine at a grocery store has an average time between Poisson arrivals of $12$ minutes. The machine processes customers at a constant rate of six per hour. What is the average time $($in minutes$)$ that an arriving customer will spend in the queue?

Answers: A$.$

$0\mathrm{.}84$

B$.$

$0\mathrm{.}42$

C$.$

$50$

D$.$

$25$