Notice how WI = 12 is one-third of IL = 36 So AM is going to be one-third of ML = 30 making AM = 10 AL = AM+ML = 10+30 = 40 AL = 40
Or a more formal way to do it is to use ratios AL/ML = WL/IL AL/ML = (WI+IL)/IL AL/30 = (12+36)/36 AL/30 = 48/36 36*AL = 30*48 36*AL = 1440 AL = 1440/36 AL = 40 Either way we get the same answer