What is an even number and what is an odd number? What is the number 0: even or odd?

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Is it possible to exchange 25 lire with ten coins of 1, 3 and 5 lire?

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Discussion here

Are there two natural numbers whose sum and product are odd?

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Bart tore the school wall newspaper into 3 parts. After that, he took one of the pieces and also tore it into 3 parts. Then again one of the pieces was torn into 3 parts, and so on. Could he end up with 100 pieces?

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On a chessboard on one of the cells stood the knight. He made several moves and returned to the same square. Did he make an even or odd number of moves?

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Numbers from 1 to 10 are written in a row:
1 2 3 4 5 6 7 8 9 10.
Is it possible to place + and − signs between them so that we get 0?

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Parliament consists of two equal chambers. All representatives of both chambers were present at the joint meeting connected with the adoption of an important decision. Due to the importance of the issue, no one abstained from voting. After summarizing the results, it was announced that the decision was made by a majority of 25 votes. The opposition shouted: "This is a hoax!" How was this determined?

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This time Bart corrected two numbers in the multiplication example.
It turned out 4 · 5 · 4 · 5 · 4 = 2247. Help teacher Ms Clayton restore the original example. (Determine which numbers were corrected for what, and explain why it could not have been done otherwise.)

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Three jars labeled "raspberry", "strawberry" and "raspberry or strawberry" were filled with currant, raspberry and strawberry jam. All labels were incorrect. What kind of jam was poured into the "strawberry" jar?

Leaflet #logic

"Pure mathematics is in its way, the poetry of logical ideas." - Albert Einstein.

#quote

When the teacher scolded Sheldon for bad handwriting, he said: "All great people had bad handwriting, so I'm a great person."
Is he right?

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Peppers were stolen from the president. As you know, those who steal pepper always lie. The press secretary said he knew who stole the pepper. Is he guilty?

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Leaflet #logic

Among four people, there are no three with the same name, or with the same patronymic, or with the same surname, but every two have the same name, or surname, or patronymic. Could this be?

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Leaflet #logic

Someone gave Winnie-the-Pooh a barrel of honey, placing it on the porch of his house. Pooh suspects that it was one of his friends: Piglet, Tigger or Eeyore. But how do you know? Each of them points to one of the other two. Only Piglet told the truth. If everyone pointed not to the one they point to, but to the second one, then Eeyore would be the only one who told the truth. Who gave the gift?

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One of the three friends gave honey to Rabbit in the same way. Piglet answered Rabbit's questions that it was Eeyore, and Rabbit forgot what Eeyore and Tigger said. Pooh took matters into his own hands and found out that only one of the three had told the truth, and he was the one who made the gift. Who gave the gift?

Leaflet #logic

Today, July 22, is Pi Approximation Day!

#celebration 🎉

Cowboy Joe bought several bottles of Coca-Cola for 40 cents each, several sandwiches for 24 cents and 2 steaks at the saloon. The bartender said it was $20.50. Cowboy Joe told the bartender everything he thought about his ability to count. Was the bartender really wrong?

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Three clown brothers Paul, François and Albert from the Fratellini family entered the arena wearing red, blue and green shirts. Their shoes were the same three colors. François's shoes and shirt were the same color. There was nothing red on Albert. Paul's shoes were green, but the shirt was not. What color shoes and shirt did Albert and François have?

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There are only two dollars in two wallets. At the same time, there is twice as much money in one wallet as in the other. How can this be?

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The castle is surrounded by a moat shaped like a rectangular frame. The width of the moat is the same everywhere. There are two boards whose lengths are equal to the width of the moat. Is it possible to cross the moat?

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Is it possible to load seven barrels of lemonade, seven empty barrels and seven half-filled barrels onto three trucks so that each truck has seven barrels and an equal amount of lemonade?

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Two trains are moving towards each other on the same railway line. A dead end departs from it, the length of which is less than the length of the train, but more than the length of one car. How do trains miss each other?

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