A mega city is one where the population is more than_____

10 million

There are two answers to this question as per NCERT Books of Class XII. As per Chapter 10 of the Book -Fundamentals of Human Geography, a Mega city is having a population of 10 million while as per the book India-People and Economy, a mega city consists of population more than 5 Million. The students are advised to keep this in mind if any question on this topic comes in actual exam. Relevant portions of the two books are quoted below for the convenience of students.

Explanation as Chapter 10- Human Settlements (Fundamentals of Human Geography) : A mega city or  megalopolis is a general term for cities together with their suburbs with a population of more than 10 million people. New York was the first to attain the status of a mega city by 1950 with a total population of about 12.5 million.

Explanation as Chapter 4- Human Settlements (India-People and Economy):Census of India classifies urban centres into six classes. Urban centre with population of more than one lakh is called a city or class I town. Cities accommodating population size between one to five million are called metropolitan cities and more than five million are mega cities.