Answer: 16 hours
Step-by-step explanation: Find the remaining number of pages David must write
24-16=8
Daniel must write 8 more pages
Find how long it takes Daniel to write one page
Since it takes Daniel an hour to write half a page, it takes him two hours to write a full page
Multiply how long one page takes by the remaining number of pages
2 x 8=16
It will take 16 more hours to write the total of 24 pages