No doubt that there have been times when GMATClubbers deftly invoke the famous "Alligation Method" in solving complex weighted averages and other ratio-related problems. When learnt properly and practiced consistently, the Alligation Method can save up to a whole minute, valuable time that is better spent on monster problems as Quant difficulty increases on your adaptive tests.
So, I am posting a journal article from 1958 that gives a basic primer on the Alligation Method. The author is so cool that he actually cites his mother-in-law as a scientific source, describing her as "....Mrs. L. F. Wilcox could beat most modern mathematicians at arithmetic, which she learned in the grade schools in upper New York State...."
Enjoy, you nerds. And please give +1 Kudos
, if you appreciate this.
PS. The main thing to remember is to reverse the ratio of the "distances" in order to find the ratio of the actual "quantities" present.
PPS. This post is purely an academic exercise and by no means a final authority on the beautiful concept that is the Alligation Method.
Der alte Fritz.
+1 Kudos me - I'm half Irish, half Prussian.