The average temperature yes, of course but it doesn't have heatwaves with peaks up to 40C like I've seen in London and other places in Europe. It certainly felt way hotter there. So I imagine you know how AVERAGE is calculated because you went to school. It's never too hot or too cold, mostly mild. It'll go from 5 in the winter to 30 in the summer, usually.
But since the city and the state are quite big, there are much colder and much hotter places, even within the city.
And I never said anything about the population, it's probably the most populated urban area in the world if you consider adjacent cities of greater Sao Paulo, with 20 million people.
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