Final answer:
In the library scenario, the arrival pattern observed is exponential. On average, the time between two successive arrivals can be calculated using the arrival rate. The average time it takes for three customers to arrive can also be calculated using the arrival rate.
Step-by-step explanation:
In the library scenario where students arrive randomly at the help desk staffed by one employee, an exponential arrival pattern has been observed. This means that the time between two successive arrivals follows an exponential distribution. On average, the time between two successive arrivals can be calculated using the arrival rate. For example, if the arrival rate is 10 students per hour, then on average, 6 minutes will elapse between two successive arrivals.
When the store first opens, the average time it takes for three customers to arrive can also be calculated using the arrival rate. For example, if the arrival rate is 10 students per hour, then on average, it will take 18 minutes for three customers to arrive.