Final answer:
The correct answer is A. Equal to. This is because under constant and steady conditions, the flow rate of customers arriving at a service point is equal to the flow rate of customers being served.
Step-by-step explanation:
The flow rate used to calculate the average number of customers waiting is equal to the flow rate used to calculate the average number of customers being served. In a simple system where the arrival rate of customers is constant and the service rate is also steady, these flow rates are balanced, assuming that there is no change in trend or any disruptions in service or arrival rates. It is important to consider consistent system conditions to ensure accuracy in such calculations. For example, if customers arrive at a rate of one every two minutes, this arrival rate would match the service flow rate if customers are also being served at that same rate under normal operating conditions.