"What is the population?"

Translation: Πόσο είναι ο πληθυσμός;

[Jon345104]

Ποιος would that work

[G.Georgopoulos]

Yes, added.

[uSCF10]

I don't understand why what is translated as πόσο. Πόσο is how much and what is just τι

[G.Georgopoulos]

"Ποιος" is also accepted, in case that's less confusing.

[Stergi3]

Why not πόσος ?

[AniOhevYayin]

I was wondering the same thing. Troll says elsewhere that Πόσο always asks for the quantity. https://forum.duolingo.com/comment/18099210 (For those wondering what we are talking about: πόσος is nominative masculine singular, so we thought it might work here in agreement with ο πληθυσμός, while πόσο is neuter nominative singular, neuter accusative singular or masculine accusative singular.)

[LarryMosle3]

I'm not clear on if πόσος is correct, too. Can it be used to agree with ο πληθυσμός?

[G.Georgopoulos]

Yes, that's correct as well.

[Efi.Stefanos]

Why not τι

[mizinamo]

Why not τι

Because then you would get an answer along the lines of A count of the number of residents within a political or geographical boundary such as a town, a nation or the world. -- a definition of the word "population", rather than a number.