Answer:
Easy! Put away your slide ruler! Just take one painter. He takes one hour to paint 1/3 of a wall.. Boy these guys must be in the union for they are really slow.. so lets assume one painter painted all 8 walls. That is a lot of cigarette breaks, it would take him 24 hours to paint all 8 walls…. But he has 3 other buddies… yea! so 4 into 24 = 6 Hours!
Explanation: