[still_grokking]

OK, maybe this is something that seems confusing for native English speakers (even I think it should not).

But your interpretation would be correctly worded as "3 hens lay each 3 eggs in 3 days".

"3 hens lay 3 eggs in 3 days" means imho completely unambiguously that "one hen lays one egg every three days".

[jhbadger]

In practice "each" is optional if it seems implied from context. I mean, if you say "Our employees work 40 hours/week" it would really be weird to interpret it as anything other than each employee working 40 hours a week rather than all employees teaming up to work 40 hours in total. Same thing with hens teaming up to lay 3 eggs. If you mean that hens lay an egg once every three days then say that and the whole thing is far clearer.

[still_grokking]

Thanks!

This finally makes sense.

Your example nails it. Now I get where the confusion comes form.

I'm not a native speaker and I guess it's not intuitive for me to insert an implicit "each" into the "puzzle" sentence. For me it sounded completely unambiguous. But if you subtextual "hear" an "each" in this sentence the wrong calculations start to make sense.

I've just tried to translate all the variants of the sentences into German (my primary langue) and indeed you would need a "jeweils" in both cases to be clear that you really mean "each". Your example with the employees would sound quite "unclean" without the "jeweils". One would understand it, but it sounds a bit wrong. But in English "Our employees work 40 hours/week" sounds just fine (at least for me).

I guess when I do calculations and "puzzles" in my head I do it in German… :-)

[mlajtos]

Sapir-Whorf to the rescue! :D