Question 4

During peak hours, the number of bus "74" arriving at the bus stop outside SUSS campus

is a Poisson variable with rate of 9 buses per hour.

Calculate the probability that you would need to wait more than 20 minutes for

the bus "74" if one bus "74" just departed on your arrival at the bus stop. Show

full details of your workings.

Briefly explain if you would be expected to wait longer at the bus stop if the bus

"74" has just departed when you arrive at the bus stop.