Mathematics [antikvár]

Groups of things that go together are called sets. Two water-melons make up a set. Three pineapples also make up a set. A bunch of green grapes and a bunch of purple grapes make up a set. Even a single melon can be called a set. We can also put tangerines and oranges together to form a single set. The idea of sets is basic to arithmetic. From now on, arithmetic will unfold in terms of the idea of sets. We shall learn how to split up a group that contains several different things. We shall learn the relations between various sets that contain different objects, and much more.