Question

An experienced housepainter can paint an inside wall in under twenty minutes. An inexperienced housepainter can take up to one hour. If a team of an experienced painter and an inexperienced painter work on a room together, what is the longest it should take them to paint the four walls, if they finish at the same time?

Answer 1

The answer is 60 minutes.

Explanation:

If the experienced painter can paint a wall in 20 minutes, and the inexperienced painter can do one in 60 minutes, then the inexperienced painter can paint one wall, and the experienced painter can paint three walls. They will both take 60 minutes and finish at the same time. Therefore, it will take them sixty minutes.

Answer 2

120 minutes
because the experienced worker would take 20*3= 60 minutes (3 walls)
and the inexperienced worker would take
60 minutes (1 wall)
60+60=120