7
6
Ten hours.
10.5 + 24k hours where k is any integer.
From 9:30 pm to 12:00 am is 2.5 hours, then from 12:00 am to 7:00 am is 7 hours. Therefore, the total hours from 9:30 pm to 7:30 am is 2.5 + 7 = 9.5 hours.
10.5 + 24*k hours where k is any integer.
From 9:30 pm to 12:00 am is 2.5 hours, then from 12:00 am to 7:00 am is 7 hours. Therefore, the total hours from 9:30 pm to 7:30 am is 2.5 + 7 = 9.5 hours.
7
6
Ten hours.
8 hours.
10 hours and 15 minutes.
10 hours and 45 minutes.
12 hours 30 minutes.
9 hours
Ten Hours
10.5 + 24k hours where k is any integer.