"Три журнала собралось" or "собрались"?

Question

How would I say "3 journals were gathered"

• три журнала собрались?

or

• три журнала собралось?

More specifically, do i decline according to три or журнала?

If I'm wrong, how should i make the sentence?

Answer 1

Because someone did the gathering, you need to use impersonal sentences:

Собрали три журнала.

Было собрано три журнала.

You would use “собрались” where the subjects actually performed the action: Школьники собрались в классе; and “собралось” where, on the contrary, it just happened: В фильтре собралось много мусора.

As for declension, you decline “три журнала” as a whole. Трёх журналов, трём журналам etc.

Answer 2

Its' the passive voice here, so It can't be собралось/собрались, which is usually (if not always) about people who gathered. Literally, it's Было собрано 3 журнала. Depending on context it could also be Забрали три журнала (где-то приготовленные). However, to gather could be used here as a printing industry term:

Gather – To assemble folded signatures in proper sequence.

https://www.pimw.org/about-us/the-printing-industry/glossary-of-print-terms/

which corresponds to the Russian term подбирать (отпечатанные) листы.

http://www.apostrof.ru/pubs/2620.html

So it could actually mean fulfillment of an intermediate operation in printing for 3 items in work:

Произведён подбор листов для трёх журналов.

Answer 3

You can't use собрались,because that presupposes animate nouns, people, but you can use собралось for things in impersonal sentence

У меня собралось целых три журнала.(accumulated).

One of the meanings of the verb is

Насчитываться, доходить до какого-либо количества, числа.

The declension of the noun depends on the numeral три. Another variant is passive voice which has already been covered in the previous answers. Both было собрано and были собраны are valid.