Blake can do the work in 9 and part of work in 1 hour = 1/9
Ned can paint the same room in six hours, as well as do part of work in 1 hour = 1/6
If they do it together = 1/9+1/6=5/118, and they can do 5/18 part of work in hour = 1
So, they can do whole work in hours = 1/5/18=3.6
So if they do it together it will only take 3.6 hours.
