Number 2 is correct, but because a lot of english speakers don't speak english in a way which is 100% grammatically correct, you will hear a lot of people making this mistake haha. I think I even do it sometimes. But for exams and when writing you should to be as correct as possible :)

As Shahin says English speakers don't always speak "correct' English. As an English speaker though, I do find "less meetings / apples / other countables" a bit "grating" on my ear, So WELL DONE YOU for getting into the habit of saying it correctly.

fewer of number - things you can count less of quantity (things you can't count) So... fewer meetings. Also fewer glasses of milk, but less milk. Less soup, more apples. Is this OK?

Hi there, You are right to say "meetings" is a countable noun. Therefore, we use quantifiers for countable nouns such as "fewer". "Less" is for uncountable nouns. We can use "less than" to compare values. (There are less than fifty participants.) However, the use of "less" is for uncountable nouns. Hope this helps. Cheers, Lance