Question

It is very difficult to find agreement about the size of the world's largest cities. Can you think of reasons why estimates vary?

Answer 1

Answer:

Although according to this study a new largest city in the world has been identified, which is with 42.6 million measured larger than the previously assumed 37 million of Tokyo, overall fewer cities achieve mega-city status (mega cities are defined as cities with >10 million inhabitants (UN, 2018)).