There are total 15 hours or 900 minutes from 1am to 4pm. In words, this duration is equal to fifteen hours or nine hundred minutes.
How many hours from
| 1AM to 9AM | 10AM to 1AM | 9AM to 3AM |
| 5AM to 4AM | 3AM to 2AM | 4PM to 8PM |
| 9AM to 11PM | 4AM to 2PM | 7PM to 7AM |
| 2PM to 11AM | 1AM to 9AM | 12PM to 10AM |
| 3PM to 2PM | 6AM to 10PM | 11AM to 9AM |
| 7PM to 8AM | 3AM to 9AM | 3PM to 4AM |
