8 hours and 15 minutes.
(8.25 + 24k) hours, where k is any integer.
36
It is 9 hours.
6 hours and 30 minutes.
2.25 assuming both am or pm
15 hours and 20 minutes.
There are 9 and 1/2 hours between 8:45 am and 6:15 pm.
6 hours and 45 minutes.
6 hours 30 minutes
6 hours and 30 minutes.
840
8 and 1/2