- Can you imagine, Tonti, - Max said, - if instead of a math lesson we had an astronautics lesson ?!

- Yeah, - Tonti said dreamily, - and there is zero gravity in the classroom: pens, notebooks, a teacher are flying around ...

- And flying past you, he says: "Shvabrin, fly to the board!"

- And I answer her: "I can not: And she told me:" Do you want a deuce? " And I told her. - "The board itself flies to me." And she “Be careful. Whatever crush you." And I ‚“ Don't yawn either. Out of the magazine, grades fly out."

- It will be quite fun here. An astronaut will fly into the classroom and say “Guys! I invite everyone to make a space flight! "

- And we all class will climb into a spaceship and fly into space!

- Let's see our Earth, so small and beautiful!
- And take a course to Mars!

- And suddenly the engines of the spaceship fail.

- Guys! - says the astronaut - Think of something! You're smart. At school learn.

- What is there to think? Let's got out and all together will push!

- It's unlikely, - the cosmonaut smiles - To push, you need to push off from something. And in space, we have nothing to push off from.

- And from the Sun? - the guys shout - Can you push off from the Sun?

- Can. But the temperature of even the upper solar layers is 5800 degrees Celsius. Shoes do not mind?

“The rocket doesn’t work because she’s hungry,” says Molly, as always. “We need to feed her. I’ll prepare everything now. Where are your groceries?

- Dear girl, - the astronaut laughs, - on the spaceship all the food is in tubes. And soup, and meat, and ice cream on a stick.
- Ahd have a stick? - asks one of the guys.

- No, no wand. But there is a popsicle with a stick.
And then it suddenly turns out that the engine has nothing to do with it, and the ship is not flying ... because he was captured by aliens and pulled into a black hole!

- What is a black hole? Molly asks.

- This is when a huge star, - explains the astronaut, - a million times larger than our sun, suddenly shrinks and becomes the size of an atom. And it attracts everything around with incredible power. Even light cannot escape its captivity. Therefore, it is called a black hole.

- Why are the aliens dragging our ship into a black hole? - asks Molly - We haven't done them anything wrong.

- They know, - the cosmonaut answers, - that all people on Earth live very together and immediately rush to our aid. And then the black hole will suck in everyone. And the planet will be free for aliens.

- What cunning, - everyone shouts, - we will not allow ourselves to be used!

- We won't! Molly agrees. - Just how?

And suddenly a space fence grows around in which there are two holes: one round, the other is square.

- The diameter of the circle is equal to the side of the square! - the astronaut determines at a distance. - If we direct our spaceship into that hole, the area of ​​which is smaller, then we will get stuck in it! And we will not fall into a black hole.

- The hole protects from the hole! - witty, as always, says Molly.

- Choosing a square!

- And I think a circle is better!

- Decide soon! - the astronaut shouts.

-… Make up your mind soon! - came the voice of the teacher. - Lesson ends! Why are there blank sheets in front of you? Where is the solution to the problem about the area of ​​a circle and the area of ​​a square?

“We were saving the world,” Tonti muttered.
“So that no one gets into the black hole,” Max added.

“I don’t know about a black hole,” the teacher said angrily, “but I promise you black friday. So that tomorrow they will come to school with their parents! To the director!

She turned around and left.

“Perhaps, I will lead my parents through a round hole,“ Max smiled.
“And I - through the square one,” Tonti answered confidently.