A challenge for the smartest.

The teacher sat down, got the tickets, the first five students came in, and the process went. By the scream of the examiner we realized that our most worrying expectations were fulfilled. The man turned out to be some serious professor and could not quietly listen to the nonsense of our poor students.
It was a brutal strike! The apophysis came when an unknown evil examiner forced our Katya, a drinking girl from a very distant depth, to write a sinus in a square plus a cosinus in a square. Katya carefully put the word "sinus" on the board with a calligraphic handwriting, surrounding it with the same flat beautiful square.

At that moment, the old man of the group looked into the audience. After evaluating the situation, she returned to the hallway, grabbed me and pushed me into the audience, telling the professor that I really wanted to respond without preparation.

The examiner accordingly sneered and pointed his hand to the chair in front of him. I sat down, picked a ticket, started answering. He opened his eyes:
Take another ticket.

I take. One theory, another one. He checked me for headphones – and I am funny. Let me load:
– Well, tell me about the cosinus theorem – three proofs right now? Yes is. This is this?

And so for an hour. But I even liked it. It was nice to prove something to this man. As a result, the satisfied examiner sat down, got my score and put “excellent.” Then I learned that he didn’t even put more than four girls on the fismat.

Why are you so stupid in your school? The man breathed. What exactly did you forget here?
“We are not stupid,” I replied. We just think differently – creatively. And in general, mathematics for primary school is sometimes more difficult than for higher school.
Is it how? I was surprised by the light.
This is so!

With these words, I went back to the hallway, took a package of books, pulled out the mathematics textbook for the fourth grade, opened where the booklet was.

- Solve this task, - and gave the book to the professor.

He began to read. The conditions are such: from the two shores of a large lake, two boats sail in front of each other. Between them, a man sails from one boat to another. He sails to the boat and turns back. The longer both boats travel, the more the distance of the swimmer is shortened. The distance between the shores, the speed of the boat, the speed of the swimmer. Question: After what time will the swimmer stop?

The uncle looked again at the cover of the textbook, grabbed a sheet and a pencil. He told the whole group to come in and prepare. Everyone ran, selected tickets and sat down, happy, to write down. The man started drawing some icks and games. My tongue was drawn out of diligence.

At first glance, it seemed that if you fold the pieces of the distance from the swimmer to the boats, you can get to the essence, then fold the periods of time, and you will get the right decision. But in fact there were too many calculations on paper, and for half an hour the professor had not yet come to the answer. Then I suggested him:
There is a simple formula: distance divided by speed, we get time. The distance between the shores is given in the task, the speed of the boat - too. Divide the distance by the speed of the boats and find out when they will stop the swimmer – in fifteen minutes.

The teaching cried out:
What about the swimmer?
What is a swimmer? I smiled. Once the boats press the swimmer in fifteen minutes, it does not matter how fast he was. This is just excess data. You see, the task with the star - for the smartest children in the fourth grade!

After that, I picked up my bags and went home, leaving the tired professor with the rest of the students. As I learned later, the exam he took well, he did not put a double. Until the end of the exam, he was in a stupa.