"We are old and hungry."
Translation:Yaşlıyız ve açız.
Eskiyiz does not refer to the age of people. It CAN be used for people, but only in limited contexts and it's a tad slangy. Like, "we're old hands at something" or "we've been here longer than you green kids." It can also be used to refer to "former." There's another exercise that says something like "eski müdür yaşlıydı" = the old (former) manager was old (aged)
According to https://www.duolingo.com/skill/tr/To-be/tips-and-notes : Aç = Hungry. Açım = I'm hungry. Açız = We're hungry. Açsınız = You are hungry (plural or formal singular).