This document discusses the most populous countries and metropolitan areas in the world. China has the largest population of any country with over 1.3 billion people, followed by India with over 1.2 billion. Tokyo is the world's largest metropolitan area by population with over 37 million residents, followed by Delhi and Shanghai which each have over 20 million residents.

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5. Source - http://www.poptens.com/2012/03/19/most-populous-countries/

6. Source - http://en.wikipedia.org/wiki/List_of_metropolitan_areas_by_population

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