A teacher of someone I know puts it like this: Let's say you have a fly in your room that you want to kill. You can do so by hitting it with a fly swatter or by shooting a canonball at it. Both are effective. Only one of them is efficient. Basically, effective means that it works, while efficient means that it works AND does not use a lot more resources than necessary.
I just want to add (since this is a Danish course) that the answers here are obviously valid for English;
- Something is effective --> it has the desired effect, i.e. it's working.
- Something/someone is efficient --> it's a streamlined process or a person getting (a lot of) things done in a short time/with little help.
I'd like to point out, however, that the Nordic languages don't have this "dualism"; We use 'effektiv' for both although I'd say it's mainly in the 2nd meaning, i.e. translating to English 'efficient'.
If you were really bothered by mosquitos one evening, then bought one of those ultra sound devices that are designed to scare aware insects, and you realised the 2nd evening that not a single mosquito is there anymore, you'd say something like "Jeez, that thingy was super effective!" in English, and you would use the word 'effektiv' in Danish also.
However, the word in Danish usually would translate to 'efficient', and I think that is always true when speaking about people; It means efficient.
While you can possibly say in English that a model is effective (she's actually causing some real effect, her track record shows that people buy whatever she's displaying), we will express it like that in the Nordics; Either we'd say that her work/commercials/advertisement is effective (has an effect on people), or we'd use the sentence from this exercise to say that she's efficient.
I have reported this exercise, as the English translation should be efficient.
(Btw: If the model was not a person, but a small scale version of a product such as a house, ship, aircraft, car or steam engine, then 'effektiv' would be slightly more likely to mean effective in English, e.g. in case we are talking about how this model can be used in education to help explaining the inner workings to the students etc.)
And final disclaimer; I'm a native Norwegian, not Dane. The consept of 'effektiv', however, is the same in all the Scandinavian languages (Finnish being Nordic but not Scandinavian :-)
The English translation is wrong - I keep reporting errora in this Danish course.
'Effektiv' in Danish (and Swedish + Norwegian) may have the meaning 'effective', although is much more frequently used for 'efficient'.
When speaking about people, the translation is always efficient.
It's a little weird sentence, but you can give it some sense. It means that she's a good model, not in the sense of wearing fancy clothes and running around on the catwalk, but as a simplified version of a principle.
For instance, let's say we're talking about the economics of a bakery and how the workers should behave in order to maximise revenue. We know of this real-life bakery with this real-life woman working in it whose style of work is close to this ideal behaviour, so we can say that she's an effective (good) model for this kind of economic theory.
No, that's not the case. The English translation should be 'efficient' in this exercise; She's an efficient model, getting on the set, quickly putting on what she's asked to display, catching quickly what the photographer & product people would like to do and getting it done in a short time. Voilà!