It is given that Paolo reaches the bus stand at 11: 45.
Now, Paolo has to get a bus by 11: 48 because it take takes 12 minutes to reach his friend which he has to reach by noon to be on time
We know that a bus comes every 5 minutes. So the probability of Paolo getting onto a bus in 5 minutes is 1.
Therefore, the probability of Paolo getting a bus from 11: 45 to 11: 48 is 60%.
This is because if probability of getting a bus in 5 minutes is 1 then, by using the unitary method, the probability of getting a bus in 3 minutes can be calculated as:
or equivalently, 60%.
Thus, 60% is the correct answer.