Question

A wallpaper hanger requires 6 h to hang the wallpaper on one wall of a room. a second wallpaper hanger requires 4 h to hang the same amount of wallpaper. the first wallpaper hanger works alone for 3 h and then quits. how long will it take the second hanger, working alone, to finish papering the wall?

Answer 1

Since the first hanger worked 3 hours on a 6-hour job, we assume the job was left half done. The second hanger can do half the job in half of 4 hours, so will take 2 hours to finish.