I hear it a lot in the UK (but Duo doesn't normally prefer British usage over US).
I know it is accepted but it said another correct solution was "Do you want a coffee".
"A coffee" is completely acceptable. To the waitress in a restaurant... "I'll have a coffee and my wife will have a tea, please."
Thats what I want to know. I used a similar translation like that on another question and i got it right!
I learned "color de café" in my Spanish class, but Duolingo used "marron" for "brown" in an earlier lesson.
Could someone please explain how "Want a coffee?" Differs from "Do you want a coffee", when the original text says: Quieres un café?
Quieres for "you" (2nd person) and quiere "he/she or a name" (3rd person).
Before I started keeping kosher and had to quit the local restaurants, all I ever heard in the "greasy spoons", was, "Coffee?" All the rest was superfluous. :) And the answer was always, "yes" or "please".
Because that translates to "you I want". You would need to use "tú quieres" (you want) or "yo quiero" (I want), but not both together.