From 6:30 AM to 7:30 PM is a total of 13 hours. This is calculated by finding the difference between the two times, which includes the full hours from 6:30 AM to 6:30 PM (12 hours) plus an additional hour from 6:30 PM to 7:30 PM.
From 7:30 to 6:30, there are 11 hours. If you count from 7:30 AM to 6:30 PM, it is a span of 11 hours.
9 hours.
10 hours and 15 minutes.
10.5 + 24*k hours where k is any integer.
If they're both on the same date, then they mark a period of 21/2 hours.
From 7:30 to 6:30, there are 11 hours. If you count from 7:30 AM to 6:30 PM, it is a span of 11 hours.
7
6
9 hours.
9 hours.
Ten hours.
8 hours.
8.5
10 hours and 45 minutes.
12 hours 30 minutes.
10 hours and 15 minutes.
10.5 hours