Plurals of numbers

Question

Is there an easy way to translate the plurals of numbers? Some seem pretty straight forward. For instance two sixes → dos seises. But what about when the number is already plural, or when pluralizing the number makes the meaning ambiguous (something that doesn't happen in English, which doesn't have plural numbers, per se).

For example... in English, one might say:

Can you give me two hundreds? (meaning two one hundred dollar bills)

In Spanish, a direct translation would be:

¿Puedes darme dos cientos?

Which is indistinguishable from Can you give me two hundred? (which could be in any denomination).

One obvious possibility when dealing with money is:

¿Puedes darme dos billetes de cien?

Is this the only possibility?

And how would someone say Two two hundreds? Dos doscientoses?

Answer 1

for the first part of your question two hundreds (2 x 100) is written "dos cientos" but two hundred (200) is written doscientos. Of course this is not possible while speaking but the context would help in that situation.

For the second part you can drop "billetes/monedas" if you are talking about money "Dos de doscientos" for "two two hundreds" and is still clear.

Answer 2

Well, those are probably not the best examples, because in Spanish you don't use bills to express quantities. You can speak about quantities:

Dame doscientos euros.

... or speak about actual bills (which is very specific):

Dame dos (billetes) de cien.

Even omitting the word "billetes" is something you can do only when you're talking about actual bills (e.g. with money in your hands). No one usually (at least in Spain) talk about amounts of money like in English with

That's going to cost you two grand.

So the translation to that one would be:

Esto te va a costar dos mil (euros).

Never use:

Esto te va a costar dos miles.

But leaving bills behind, when referring to a number as a noun (e.g. you're looking for two copies of the number one hundred from a series of comic books, or lottery tickets), you cannot say (nor write):

Dame dos cientos.

Only in this particular case (using cien as a noun) you must say:

Dame dos cienes.

And I say "only" beacuse in any other case (quantities) is a common error. If you were to talk about hundreds of people you should say cientos/centenares de personas as showed on RAE:

No existe el plural cienes, salvo para hacer referencia al guarismo [la cifra]: Escribe dos cienes en este papel. Así pues, es incorrecto un ejemplo como el siguiente: *«No se les ocurra incrementar los precios de la canasta básica, porque mataría de hambre a cienes de nicaragüenses de clase humilde» (Prensa [Nic.] 12.5.97); debió decirse cientos de nicaragüenses.

As for the other numbers you have to use the current formation of plurals, as showed on bullet #5, RAE:

Cuando se usan como sustantivos, los cardinales sí presentan variación de número y adoptan el plural que les corresponde según su forma (ceros, unos, doses, treses, cuatros, cincos, seises, [...] dieces, onces, doces, treces, etc.): «Toda la historia empezó con una partida de dados, si antes de la tercera salen cinco seises te mato» (Cela Cristo [Esp. 1988]); «El cazador Rosario me sirvió cinco cartas: me tocaron tres doces» (Scorza Tumba [Perú 1988]).