I am working on this problem and I don't really know how to use the information given.
Interarrival time (min) 15-6-12-13-9-14-9-7-15-14-11-12
Service time (min) 11-15-10-14-7-15-13-14-2-14-6-16
I'm supposed to calculate the average waiting time and some probability but I'm stuck because I can't figure out to calculate the mean service time (µ) but I've never done that from using a table. We have always been given the mean service time.
English isn't my first language and there isn't much information to be given in my native one.
Is there a formula that I'm over looking? I have calculated the arrival rate, (λ) from this, and I think I've done that correctly. λ = 5.22 customers/hour
EDIT: The shop opens at t = 0 and closed after the last customer left.
Any help would be appreciated.