Both Duo and SpanishDict say eficaz can mean either effective or efficient. "Simple, pero eficaz" is a statement out of context, but "simple" could imply less waste, and for that reason I chose the translation, "Simple, but efficient", and was counted wrong. I am reporting it. Both effective and efficient have the Latin root efficere, but efficient potentially can connote less waste. They are listed as synonyms in dictionaries.
Please, tell me what the difference between "effective" and "efficient", I put "efficient" here, because I don't know the difference.
effective: successful in producing a desired or intended result
efficient: achieving maximum productivity with minimum wasted effort or expense
The DL hint for eficaz shows both effective and efficient as being valid.
In English, this sentence would work with either word. Granted, they're two different ideas - which would totally depend on the context of what you were trying to confer.
DL marks "efficient" as wrong, even though there is no context to this sentence.
@schm00 - I don't know why you've been downvoted, the DL hint does show eficaz as meaning efficient as well and so both efficient and effective should be accepted in my eyes.
Efficient is listed as a definition of the word when you mouse over. It should be accepted.
GOOD JOB!!! You almost have 1500 day streak Hroes!
ef·fi·ca·cious ˌefəˈkāSHəs/ adjectiveformal (typically of something inanimate or abstract) successful in producing a desired or intended result; effective. "the vaccine has proved both efficacious and safe" synonyms: effective, effectual, successful, productive, constructive, potent;
Lily the Pink's medicinal compound was "most efficacious in every case". Perfectly good word but not nearly as common as 'effective'.
Just because a word is not as commonly used does not mean it is an incorrect translation.
Sorry but I don't understand why "efficient" is not a correct answer... I need you! If you are talking about a person, is it incorrect to say: "Simple, pero eficaz" ?
I used the word "efficacious" which is not only a valid answer but listed under eficaz as one of its translations, and my translation was still marked incorrect. Not cool, Duolingo.
Sencillo - plain, simple, without flourish
Simple - easy, simple, without obstacles
I deliberately translated the sentence as 'simple but effectual' in the expectation thst Duo would reject it. It did. I wonder if English is the only language to have such similar words as 'effective' and 'effectual' with very slightly different meanings, which vary according to which usage book one consults.