"Where are the fork and the plate?"
Translation:Missä haarukka ja lautanen ovat?
Duolingo always has one or max. two translations as the best ones, and if you use another permitted one it will show you that best one just to maybe steer you that way.
Technically, "on" is wrong here, because you have two items and it should thus be "ovat". But I guess many people (especially when speaking) are lazier than that and just go for "on", and that's why that's also accepted here. But if you ask me, that's being too permissive ;-)