Working? alone, a person a can paint a room in 4 hr. person b can paint the same room working alone in 6 hr. how long will it take them if they work? together?
We will express the work done relative to time thus, person a = 1/4 person b = 1/6 Since two of them will work together and then add the two. total work = person a + person b = 1/4+1/6 =(3+2)/12 =5/12 hours in hours 1/t=5/12 hours total time = 2.4 hours or 2 hours and 24 mins. The total time that person a and person b when working together will make the work done in 2.4 hours.
