As pm is noon - there are eight hours and eighteen minutes - assuming it is from noon to 8.18pm in the evening.
If it is from noon to 8.18 am the following day, and using the 24 hour clock, then it would be twenty hours and eighteen minutes.
Note: It is not precise enough in the question.
12 Hours ! There are 12 hours in the AM and 12 hours in the PM !
12 hours
12 hours
From midnight (am) to Noon (pm) is 12 hours.
2.5 hours
2 hours
3 hours
7 and a half hours
21 hours
2 hours.
6 hours.
There are 16 hours from 4 am to 8 pm. 4 am to 4 pm is 12 hours, then 4 pm to 8 pm is another 4 hours.