1.5 hours.
7 hours
22
2hrs and 30mins
11am to 12 is 1 hour 12 to 5pm is 5 hours → 11am to 5pm is 1 + 5 = 6 hours
71/2 hours IF they're both in the same day.
8 hours.
7 hours
22
7 hours and 30 minutes.
2hrs and 30mins
72
9 + 24k where k is an integer.
On the same morning there are 3 hours from 8am to 11am
4 hours and 15 minutes.
11am to 12 is 1 hour 12 to 5pm is 5 hours → 11am to 5pm is 1 + 5 = 6 hours
7 and a half
2 hours