Arithmetic is a subject. Which is not to everyone's liking, many consider it optional when there are numerous devices with calculators. In fact, mathematics can calculate literally everything that happens in our world, for this there are a lot of formulas and theorems. But this is already higher mathematics, and you need to start with a simple, elementary as in Elementary Arithmetic Math. Examples will appear on the screen in which there are not enough arithmetic signs: plus, minus, division and multiplication. You must add them, taking from the set of examples and transferring to the place.