Translation:I am going to offer you five big ones.
Five big ones?? Setting aside the oddness of this sentence (a response from a t-shirt vendor when asked what you can buy with $20?) where does the "ones" come from? Does "grandes" mean "big ones"? I lost my last heart with "I am going to offer you five larges", so yes, I'm bitter. The owl cried. Then I cried. You know how many tears? Five big ones!
Sounds like a perfectly reasonable sentence to me. "How many fish can I get for $50?" - "I will offer you five big ones". This use of adjectives in this way is common in Spanish. If you see an adjective by itself like that, you normally need to put "one" or "ones" after it in English. "Los rojos" = "The red ones". "El largo" = "The long one", etc.
This sentence needs to be removed. I, too, lost a heart with the translation "I am going to offer you five grand". There is absolutely no way we could have know to translate grandes as "big ones". I really appreciate the Duolingo tool and it has helped me learn alot, but it also often confuses me with really bad translations that don't make sense or can't be deduced from the knowledge gained to date.
My original post proposed an almost identical example involving t-shirts, but your example changes the translation from "I am going to offer" to "I can offer" to make it sound less clunky and more like something someone (other than "the Godfather") might actually say. But more to the point, even if this sentence makes sense in Spanish, most of us had no idea that "grandes" translates into "big ones" because how would we? At least back when I hit this question, it wasn't offered as a hint.
You're not going to learn Spanish just using DuoLingo. It has some good exercises, but doesn't really provide much in the way of instruction. You really need to use other sources too. I highly recommend SpanishDict.com, LoMasTv.com, studyspanish.com, and spanish.about.com. To really advance you should consider getting a teacher. Check out BuddySchool.com - lots of people willing to teach you Spanish via Skype, at very cheap prices.
Just because you don't like the solution offered, doesn't mean that the sentence should be removed. You now know how to 'offer five big ones'. And, btw, I deduced the correct answer (without using translation websites), so there is a way that someone can figure out that grandes translates to 'big ones'.
please, we understand that in a certain context, this sentence could be grammatically and functionally correct. in the case of learning a new language, however, it has thrown the majority of us for a loop, but not in the way learning some revolutionary language trick or tip would. there is a time and a place for these words/phrases/concepts to be introduced, but the majority here are just saying this is not the time for this phrase. no need to defend it more, we're all learning.
Actually it is an important thing to learn. The use of "grandes"which is similar to a piece of English slang is unfortunate, but Spanish speakers use this type of construct all the time. If you see an adjective by itself you basically need to add "one" or "ones" in the English translation.
"Los rojos" = "The red ones".
"El largo" = "The long one".
"Un grueso" = "A fat one".
"Unos pequeños" = "Some small ones".
"Los nuevos" = "The new ones".
"Cinco grandes" = "Five big ones".