"Ella tiene unos cuantos amigos."
Translation:She has some friends.
Nope. This sentence is really akward for a non-native. Even the translation given by DL is not so correct, "unos cuantos" means "a few" and "quite a few"; did I say you that was akward?
Then, how do you know when the talker is saying one thing or the opposite? By the intonation. When you want to say "quite a few", you do a more empathic intonation.
Well, if you're reading a novel, or anything published, it'd likely be explained by the author. If it were just dialogue, it may be more tricky, but there's a good chance you could still figure it out from the context.
It's similar, but that would more likely be translated as "Ella tiene un número de amigos" or "Ella tiene varios amigos".
I'm not sure about the Spanish idioms, but in English "She has a number of friends" means that she has "some friends". She has enough to count, but nothing more definite about the quantity is intended.
I think "a number of ____" typically means that the quantity of whatever is being discussed is quite large, so I'm not sure "unos" would be the most precise translation. "Mucho" would probably be more appropriate.
unos cuantos is repetition at best, and contradictory at worse -
unos a few / cuantos many
The best translation of "unos cuantos" is "a few" ("some" also works). Just like in English "a few", the emphasis here is that it not none.
How does this compare to "pocos amigos"? In an earlier question, "pocos amigos" translated to "a few friends". So can "unos cuantos amigos" and "pocos amigos" both mean "a few friends"?
I'm guessing, but here's what I think: "unos cuantos amigos" would be in answer to the question, "Does she have ANY friends?" and "pocos amigos" would be the reply to "Does she have a lot of friends?" The emphasis is different, depending what you're comparing it to. Someone who's fluent--can you tell us if this is right?