I was almost forgetting about that 'des'='de' in negative sentences. Just in case someone else has the same question.
"In a negative construction, the partitive and indefinite articles (singular and plural) change to de, usually meaning '(not) any'"
I think both solutions should be acceped because...
If the questions are :
As-tu une solution ? Non, je n'ai pas de solution ;
As-tu des solutions ? Non, je n'ai pas de solutions.
According if we have a " s " or not, we could suppose how the question is. That seems to me more logical and more convenient.
Yeah, I am wondering why this is written in plural French. The spoken French is obviously ambiguous as to solution(s). The French also tends to bring the negative to a singular as in 'de' vs 'des'. Seems to me that the French phrase is written wrong, but this won't effect my speech.
Bonjour Lisa. The reasons would be that Duo doesn't provide an exhaustive list of translations/hints; and we can't always rely on the hints to be correct. As you note, 'about' and the other hints provided don't work, so I used a bit of logic: 'the solutions' would be 'les solutions' while 'a solution' would have been the singular 'une solution.' 'Des solutions' would be 'some solutions,' which sounds wrong in English and isn't correct in French grammar as noted previously. Also noted previously, it's not 'une solution' since the sentence uses a plural. in English grammar, 'I don't have solutions' isn't usually used, but 'I don't have any solutions' is a perfectly respectable English excuse. Sentence. Whatever... :)
Like many comments here, I find it bizarre that translations using the singular are not accepted. In the audio, there is no way of knowing "solutions" is plural. I put "I do not have a solution" even though I know "de" often means "some" or "any", because it didn't fit with the singular. Marked wrong of course!