How many ports do we need to have inorder to have the least amount of Blocked calls due to the not sufficient ports(would like to know how many ports is needed so when customers call they don’t get busy signals and there is always enough ports for them) if:
1) When we have just 8 hours traffic in a day.
2) When we have 80 min in average for each 10$ phone card.
3) Let’s say when we want to have 1200 phone cards sold in a month.