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.
