Question 22
Coky and Boby together can paint a room in 8 days, Andy and Boby together can do it in 6 days, Andy and Coky together in 4 days. What is the number of days does it take all of them working together to paint 4 identical rooms if Coky absent only in the second day when paints each room and Boby absent from the third day to the end when paints each room?