Scientists insist that mathematics is one of the best exercises for our brain. It is interesting, what useful can be not only complicated calculations but also simple puzzles, which can often be found online.

We **AdMe.ru** like to test yourself with brainteasers, so we offer you to solve a few equations that went viral recently.

1. On Twitter arguing over school puzzles

Recently, hit was simple at first glance the equation. To argue the users of social networks have begun due to the refinement of the author of the tweet: “It’s a mathematical meme that is actually funny, not stupid. You probably don’t believe it, but the answer is 5!”

Most people think that the correct answer is 120. But Professor of mathematics continue to insist that 230 — 220 × 0,5 = 5! Who is right?

2. One more equation, which divided the Internet into 2 camps

There are 2 common answers: 1 and 16. Even calculators confused:

Whose side are you on?

3. Test care

In Hong Kong, this task should be able to solve pupils of the 1st class.

4. On what principle is this?

5. The task of the cartoonist, who was famous for his puzzles

Maybe you remember the equation that will further confuse people? If so, share them with other readers. Who knows, maybe your task will become a new Internet hit.