Question

It takes Ms. Campbell 5 times as long as it takes Ms. Dorsey to paint a room. If Ms. Dorsey helps Ms Campbell, they can paint the room together in 4 hours. How long does it take them individually to paint the room?

Answer 1

Ms. Campbell= 24 hours

Ms. Dorsey = 4.8 hours

Explanation:

Ms. Campbell paints 5x slower compared to Ms.Dorsey. Let's say Ms.Dorsey paint 5 meter square per hour, then Ms. Campbell paints 1 meter square per hour.

When they work together that means their work speed will be 5 +1 = 6 meter square per hour. If they work for 4 hours, then the room area will be: 4 hours * 6 meter square per hour = 24 meter square.

If Ms. Campbell paints the room alone, the time needed will be: 24 meter square / (1 meter square /hour) = 24 hours.

If Ms. Dorsey paints the room alone, the time needed will be: 24 meter square / (5 meter square /hour) = 4.8 hours.