"Вихiд" (= Russian "выход") is a bit of culinary jargon and it roughly means "output", i.e. the weight of a cooked dish as opposed to the weight of its fresh ingredients. In this case they use it as a synonym of "portion".
All prices are given per portion, and indicating weights in grams for every portion is very common (it helps a customer to judge the size of a portion s/he will be given).

For dishes, that can be easily divided into a few main ingredients, they sometimes tell you how much of each ingredient is in a portion, or how much of it is a "main dish", and how much of it is garnish or sauce. For example, "Pancakes with strawberries 250/70" means that every portion consists of 250 grams of pancakes and 70 grams of strawberries.