"QuickMath" Game

In school, children learn all kinds of sciences that are sure to be useful to them in their adult lives. One of these sciences is mathematics, which is indispensable in everyday life! In this game you need to pull together and remember everything you learned in math class at school. Take a simple test for knowledge of mathematical rules, theorems and axioms. On the screen in front of you will appear different mathematical equations. Your task is to solve them on a piece of paper or in your mind and choose the right answer. No need to try to guess the answer, because that would be, at the very least, unfair! Keep in mind that you can go to a new task only after you solve the current one. Choosing the wrong answer means losing the level!

Choose the correct answer.