nine
18:30 - 09:30 = 09:00
0:30 + 2:00 + 6:30 = 9:00
9 hours.
There are 9 hours between 630 am and 930 am.
4 hours and 15 minutes.
This is equivalent to 16 hours.
9 hours.
9h 15m
8.5
10.5 hours
7 and a half hours
10 & 1/2
There are (7.5 + 24k) hours where k is an integer.
11 hours and 45 minutes.