Assorted means “of various different types,” usually sitting together as one set. A box of assorted biscuits has several flavours in the same tin; assorted fruit is a mix, not one kind. You see it constantly on packaging and menus, a little more shop-like than mixed. It does not tell you the types are carefully chosen — only that they are not all the same. Though actually, people also stretch it to people and objects that just happen to be together: “an assorted group of tourists.” And ill-assorted is the unkind cousin: two things (or two people) that do not go well as a pair. The word is comfortable in shops and in slightly formal writing; kids more often just say different kinds.