From 8:30 AM to 4:15 PM, there are 7 hours and 45 minutes. This can be calculated by counting the hours from 8:30 AM to 4:00 PM (which is 7 hours) and then adding the additional 15 minutes.
4.5 hours
ten and a half
If they're both in the same day, then it's 71/4 hours.
1960
9 am to 4:15 pm is approximately 7 hours and 15 minutes.
7.25
8 hours and 15 minutes.
8 hours.
4.5 hours
840
Nine and a half hours.
Nine hours.
ten and a half
If they're both in the same day, then it's 71/4 hours.
It is (8.5 + 24k) hours where k is an integer.
8:30am to noon is 3.5 hours.
8 hours and 30 minutes.