The secret of the trick with a cube in your hand. Dice trick

In this simple trick you show your super clairvoyant abilities . The spectator puts the cube in the box, remembers the number and gives it to the magician. An eye is drawn at the bottom of the box; after looking into it, the illusionist names the number that the viewer remembers. And this is repeated several times, everyone is simply amazed at your abilities. Everyone begins to examine the box, suspect each other of hinting and look at you with surprised gasps, how?

I'll say one thing than easier focus, the more impressive it is, this is a trick just from this category. It can be repeated many times in a row, the viewer will not guess anything. It is easy to perform for both children and adults.

The secret of the trick is very simple and easy. We must discreetly peek at the number at the moment when we put the small box into the large one. After all, the lid is translucent and we see a cube with a number. Watch the video and you will understand everything.

If you present even the simplest trick correctly, it will be much more successful than a trick that is performed perfectly, but without artistry. Practice, come up with your own speech and gestures, with the help of which you will present your speech.

Dice are as old as playing cards. A die is a cube with numbers from one to six, marked on the faces of the cube and arranged in such a way that their sum on opposite faces is seven. It is this principle that underlies tricks with dice.

GUESSING THE AMOUNT

The person demonstrating turns his back to the audience, and at this time one of them throws three dice onto the table.

The spectator is then asked to add up the three numbers drawn, take any die and add the number on its bottom side to the sum just received, then roll the same die again and add the rolled number to the sum again. The demonstrator draws the audience's attention to the fact that he can in no way know which of the three dice was thrown twice, then collects the dice, shakes them in his hand and immediately correctly names the final amount.

Before collecting the dice, the person showing adds up the numbers facing up. By adding seven to the resulting sum, he finds the final sum.

GUESSING THE NUMBER OF POINTS DROPPED

Many interesting dice tricks involve the positional way of writing numbers. Here is a typical one of these tricks.

The spectator throws three dice, and the shower does not look at the table. The number rolled on one of the dice is multiplied by two, five is added to the resulting product, and the result is again multiplied by five. The number rolled on the second die is added to the previous total and the result is multiplied by ten. Finally, the number rolled on the third die is added to the last number.

As soon as the shower knows the final result, he immediately calls out the three numbers drawn.

From last date the one showing subtracts 250. The three digits of the resulting difference will be the required numbers rolled on the dice.

ARITHMETICS ON CUBES

Five wooden cubes need to be drilled through the center of one of the faces.

On the non-drilled faces of three cubes we will draw numerical symbols in the form of dots, on the fourth cube - addition, subtraction, multiplication and division signs, and on the fifth - equal signs. After this, into the holes of those cubes on which the signs of arithmetic operations and the equal sign are applied, we insert axes with glue so that their ends protrude on each side by no more than half the length of the edge of the cube.

It would seem that there are only four numbers and four arithmetic operations. But try to assemble the cubes in such a sequence that arithmetic operations are performed simultaneously on all faces. Out of several thousand possible combinations only two options represent the correct answer.

This trick is incredibly easy to perform and interesting to watch. For beginner illusionists, this is a great way to show off your skills while honing your sleight of hand. A child will quickly learn it too.

What's the trick?

The trick is as follows. The magician shows 2 cubes (“dice”) sandwiched between the index and thumb. The observer must remember number combinations on the dice - those on top (in the normal position of the hands) and below (when the magician turns his hand over).

Let's say there are 6 and 3 on top, and 2 and 2 on the bottom. Then the performer turns his hand with the dice over again and again shows the viewer the combinations of 6 and 3. Then the observer is asked the question: what numbers are on the bottom? Naturally, the viewer answers “2 and 2.” The magician turns his hands over, and there are other numbers - 4 and 1.

Returning the cubes to their original position, the combination on top is again 6 and 3. You can change the position and combinations endlessly.

What's the secret?

The secret of the trick is elementary and, as in most magic tricks, lies in sleight of hand. While turning the hand, you need to turn the cubes themselves, by 1 edge.

This must be done quietly and quickly. And it only takes a few repetitions to get the hang of it. You can watch the trick itself and its secret in the video.

Focus with dice This is a simple yet effective mathematical trick. To demonstrate this trick, you will need three dice and a dark scarf or towel that can be used to blindfold the presenter. Because the we're talking about about math trick, then middle-aged children can show it school age who can add two-digit numbers well in their heads.

How to perform a trick with dice.

For demonstration trick with dice The magician-host invites one of the spectators. The viewer gets the most important role. First, the spectator must cover the magician's eyes with an opaque scarf or towel. The magician should not see what the invited spectator will do next with the cubes. To be convincing, the magician may even turn in the other direction.

So, the magician, blindfolded, asks the spectator to throw three dice and count the sum of the numbers that appear. The viewer must remember the resulting number and, of course, should not say it out loud! After this, the magician asks the spectator to turn over any two of these three dice and add the new two numbers from the inverted dice to the already memorized amount. After this, the spectator must ask for these two inverted cubes again and add the new two numbers to the sum. Final stage- third cube. The spectator turns it over and adds the number to the sum again. Next to this, he rolls the third die separately and adds the rolled number to the total.

Now the magician can turn around and untie his eyes. The magician looks at the lying dice and, to the surprise of the audience, names the total amount that the audience received after the manipulations described above.

The secret of the dice trick

The secret of the dice trick simple enough. The magician looks at last combination numbers on the dice, adds them up and adds the number 21 to the resulting sum. The resulting sum will coincide with the number given by the audience.

How is this possible since the dice are thrown randomly?! Where does the number 21 come from? If you take a die in your hand and look at it carefully, you will notice that the numbers on opposite sides of the die always add up to the number 7. For example, 5 and 2 are located on opposite sides, or 1 and 6, or 3 and 4 21 is obtained because this trick uses three dice. 7 x 3 = 21. This is the main secret.

Display Tip math trick with dice. This trick will be successful only if the audience does not make a mistake in their calculations. Therefore, if there are several spectators, then it is best to use not one, but several or all spectators in the focus. Let only one person roll the dice, but each spectator calculates the sum in his head.

Demo example math trick with dice.

1) For the first time, the spectator throws three dice, on which three random numbers appear, for example: 3 + 4 + 4 = 11

2) Now the spectator turns over two dice, for example the last two: 3 + 3 = 6

3) Now the spectator re-throws the two dice turned over at the previous stage and receives two random numbers on them, for example: 1 + 5 = 6

4) The spectator turns over the remaining third die: 4

5) The spectator rolls the third die and receives random number, for example: 2

By the time the magician's eyes are untied, the dice will have the following numbers: 2+1+5= 8

Viewer calculation result: 11+6+6+4+2 = 29

Magician's calculation result: 8+21= 29

Magic tricks as a teaching tool are rarely used in educational process. Using them in mathematics lessons and in extracurricular activities continue development logical thinking, spatial imagination, the ability to think outside the box, and also increase interest in the subject.
A trick is a skillful trick based on deceiving the eye with the help of deft and quick techniques.
The first tricks appeared at the dawn of humanity. Ancient man tried to comprehend and understand the world, unravel its secrets. The dark, illiterate masses considered magic tricks a manifestation supernatural powers gods or devil. An ancient Egyptian papyrus has survived to this day, telling the story of a wandering artist who amazed Pharaoh Khufu with his tricks. This was around 2900 BC.
Some of the first professional magicians were priests - intermediaries between people and gods. Everything was in their hands, including brilliant inventions contemporaries, unknown and incomprehensible to the large flock. And incorrectly understood phenomena replenished their stock of mystical ideas. Everything that was inaccessible to reason, everything that frightened with mystery, seemed to be a manifestation of some unknown forces.
Even then, the priests kindled a fire on the altar, and the heavy doors of the temple slowly opened by themselves, and appeared in puffs of smoke. majestic figures. The secret was simple. Hidden under the altars was a small copper cauldron filled with water. The fire made the water boil, and the steam set in motion a simple mechanism that opened the doors.
In the Middle Ages, superstitious clergy began to burn magicians at the stake as allies of the devil. Hundreds of years have passed since then. The performances of magicians have long lost their air of mystery and have simply become a brilliant demonstration of human ingenuity and dexterity. New discoveries in mathematics, physics, chemistry and other sciences were always immediately adopted. They were on the other, invisible side of the focus, and their presence was carefully guarded.
The focus is always half hidden from the audience: they know about the existence of that secret half, but imagine it as something unreal, incomprehensible. This back side Focus is based either on manual dexterity or on a variety of assistive devices. Many of them are also based on various mathematical, physical and chemical laws, although it seems that, on the contrary, they violate all well-known laws.
Mathematical tricks are observable experiments based on mathematics, on the properties of figures and numbers, presented in a somewhat extravagant form. They combine the elegance of mathematical constructions with entertainment.
Mathematical tricks are a kind of demonstration of mathematical laws. If during educational presentation they strive to reveal the idea as much as possible, here, in order to achieve efficiency and entertainment, on the contrary, they disguise the essence of the matter as cunningly as possible. That is why instead of abstract numbers they are so often used various items or sets of objects associated with numbers.
The amazing is not born in a vacuum. It, driven by a person’s fantasy, always grows out of what is already known.
The success of each trick depends on good preparation and training, on the ease of performing each number, accurate calculation, and skillful use of the techniques necessary to perform the trick. Such tricks make a great impression on the audience and captivate them.

2. Focus “Spots on the edges”
The magician invites you to secretly throw three dice onto the table, bring them together in one row, and promises to guess the number of spots that appear on the top edge of the first, second and third dice. First, he asks to write these numbers in a row and assign three more numbers, determined by the number of spots on the lower faces of the cubes, in the same order. A six-digit number is formed. The magician offers to divide this number by 111 and tell him the quotient.
For example, let the picture of the top faces of the thrown dice be as shown in the figure.

<Рисунок 1>

With the assigned numbers (from the bottom face) the number 351426 was formed. Divide by 111 and tell the magician the result: 3166. The magician declares: the numbers appearing on the upper faces of the cubes are 3, 5 and 1.
Explanation. For this trick, you must always use cubes, the sum of the numbers on opposite faces of which is 7. From the announced number, the magician always subtracts 7, dividing the difference by 9. In the quotient, you get a three-digit number, the numbers of which are the desired ones (in this example, 3, 5 and 1) . Using the algebraic form of writing a number, the resulting six-digit number with digits A, V, With, 7 – A, 7 – V, 7 – With, let's write it as
N = 105A + 10 4 V + 10 3 With + 10 2 (7 – A) + 10 1 (7 – V) + 10 0 (7 – With) =
= 10 5 A + 10 4 V + 10 3 With + 10 2 (7 – A) + 10(7 – V) + (7 – With).
Further actions: (N: 111 – 7): 9 brings the magician to the number 100 A + 10V + With(see for yourself!), the numbers of which are A, V And With. Therefore, guessing will always be unmistakable.

3. Focus “How many points did you get?”
Turning away, ask someone to throw two dice, on each of the six sides of which is written one number from 1 to 6. Then ask for double the number of points on the top side of the second dice. Based on the announced result, you can immediately name the number of points on the top edge of each dice.
Explanation. It is necessary to subtract 25 from the announced number, then the first digit of the resulting difference will be the number of points that fell on the first die, and the second – the number of points that fell on the second cup.
For example. Let the points 2 and 4 come up when throwing two dice. Performing the proposed arithmetic operations sequentially, the result will be
(2 × 2 + 5) × 5 + 4 – 25 = 24,
How can we see that the first digit of the number 24 is the number of points rolled on one die, and the second digit – number 4 – is the number of points rolled on the other die.
As a result of throwing two dice, let the numbers of points rolled on the dice be respectively equal A And V. Multiplying a number A by 2 and adding 5, we get the number 2 A+ 5, multiplying this number by 5, we get the number 10 A+ 25 by adding the number to it V and subtracting 25, we have the number

,
<Рисунок 2>

which means that the first number is the number of points rolled on the first die, and the second number is the number of points rolled on the second die.

5. Focus “Three-digit numbers”
To demonstrate this trick, five dice are taken, on the sides of which various three-digit numbers are depicted, for a total of 30 numbers. Our five bones bear the following numbers(Table 1).
The spectator throws the dice on the table, and the person showing immediately explains the sum of the five numbers that came up.
Explanation. To get this sum, the showman adds the last digits of all these numbers and subtracts the resulting number of 50. By placing the found difference in front of the subtracted one, he receives a four-digit number, which will be the required sum of the five three-digit numbers rolled on the dice. Let's say, for example, that the sum of the last digits is 26. Subtracting 26 from 50, we take 24 and the answer will be 2426.

Table 1

6. Trick "Bones and matches"
The demonstrator, turning his back to the audience, asks them to form three dice in a column, then add the numbers on the two touching faces of the top and middle dice, then add to the result the sum of the numbers on the touching faces of the middle and bottom dice, and finally add another number to the last sum on the lower bone. Finally, the column is covered with a scarf.
Now the speaker turns to the audience and takes out a handful of matches from his pocket, the number of which turns out to be equal to the amount, found by the viewer when adding five numbers on the faces of the cubes.
Explanation. Once the spectator has added up his numbers, the person showing momentarily turns his head over his shoulder, ostensibly to ask the spectator to cover the column with a handkerchief. In fact, at this time he manages to notice the number on the upper edge of the upper cube. Let's say it's a six. There should always be 21 matches in your pocket. Having grabbed all his matches, the demonstrator, taking his hand out of his pocket, drops six of them back. In other words, he takes out all the matches without as many as the number at the top of the column. This number of matches gives the sum of the numbers on the five faces.

<Рисунок 3>

It certainly closes one or the other facet. Of course, if the performer masters the technique of turning the cube well enough, then the trick can be performed without a scarf. Then the trick looks more effective, but it is more difficult to perform.

8. Trick “Cube, hat and scarf”
The magician goes on stage wearing a hat and carries a dice measuring 8x8x8 cm in his hand. He takes off the hat and places it on the table with the hole facing up. Shows the cube again from all sides, and then places it on the table. He takes a wide, opaque handkerchief out of his pocket and covers it with a cube lying on the table. Under the scarf, of course, the outlines of a cube emerge. The magician puts a hat on it, lying on the table (also with the hole facing up), makes a magic pass, lifts the hat and rolls out a cube from it. He quickly puts on his hat, moves his scarf - there is nothing under it. The audience gets the impression that the cube lying on the table passed through the scarf and ended up in the hat.
Explanation. The cube brought out by the magician was not quite ordinary. A case was pulled over it

<Рисунок 4>

In this case, the case does not have one edge (instead of this edge there is a hole into which the cube is pushed); the second face, adjacent to the first, exactly matches the pattern with one of the faces of the cube; the four remaining faces exactly coincide with the decorative circles drawn on all faces of the cube. As for the faces of the cube, inside the decorative (drawn) circles on all its faces there are drawn points - one or another number of them for each face of the cube. Now, it is probably clear that under the scarf it is not the cube itself that is placed on the table, but a case, placed with the side facing the audience, which is indistinguishable from the corresponding face of the cube.
Let's look at how the cube ends up inside the magician's hat. Before going on stage, the magician slides the cube into its case, and from afar it seems to the audience that the cube is an ordinary one. However, when the magician moves the hand holding the case with the cube through the air over the hat lying on the table, he slightly loosens the pressure of his fingers, and the cube falls out of the case and into the hat. At this moment, the case should be turned towards the audience with the side that exactly coincides with the corresponding side of the cube. The case from under the scarf disappears as follows. A piece of fishing line with a fishing hook at the end is attached to one of the edges of the case. When the magician places the case on the table, intending to cover it with a handkerchief, he hooks this fishhook to the tablecloth on the table; when the magician moves the handkerchief, he brushes the case off the table, and it hangs on the side of the table opposite from the viewer, and it seems to the audience that the “cube” has really disappeared. Viewers shouldn't notice fishing hook while showing a case with a “charged” cube inside it. You need to clamp the hook between the fingers of the hand holding the case with the cube.

9. Trick "Clock and dice"
The person showing turns away from the table, and at this time the spectator throws the dice and thinks of some number (preferably no more than 50, so as not to delay the trick). Let's say it's 19. Next, the viewer begins to touch the numbers on the dial, starting with the number indicated by the die and moving clockwise. The number on which the last 19th touch will occur is recorded. Then he makes 19 touches again, but in the direction reverse movement clockwise, counting them from the same number as the previous time. The number on which the last touch will occur is recorded again. Both written numbers are added, and their sum is called rumor. After this, the person showing immediately names the number that fell on the dice.
Explanation. The two results to be added are placed on the dial symmetrically with respect to the diameter passing through the origin (indicated by the die). Since the clock scale is uniform, the sum of the results is equal to twice the number at the beginning of the countdown, if you replace 12 with zero, 11 with 1, etc., which means that if the result is greater than 12, then subtract 12 from it, and then divide the resulting difference in half.
If the named sum is less than or equal to 12, then to get the answer you just need to divide it by 2. If the sum is more than 12, then the person showing first subtracts 12 from it, and then divides the remainder by 2.

10. Focus"A trick with dice"
The fact that the sum of the numbers on the opposite sides of a die is always seven explains many unusual mathematical tricks with dice. Here is one of the best.

<Рисунок 5>

Turn round when somebody throws three dice. Ask him:

1. to add all the three numbers;
2. to take one die and add the number on the bottom face 1 to the number which he has already counted;
3. to throw the same die again and add again the number it shows on top.

Now turn round and tell your friends that you can’t know which of the three dice they threw again. Take all the dice, shake them in your hand a moment and then tell the correct sum (Fig. 215).
How do you know? That is simple. You must add the numbers on the top faces 2 of the three dice before you take them in your hand, and add seven. If you think a little, you will understand why this works.
1 on the bottom face – on the bottom face,
2 on the top faces – on the top faces.

Literature.

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