## Posts Tagged ‘10 mentalist maths tricks’

## Trick 1: The Great MATHoudini

September 18, 2018## Trick 1: The Great MATHoudini

November 30, 2012# .

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# The Great MATHoudini

### Requirements: 1 phone book, Great showmanship

### Start by handing one member of the class a sealed envelope. It contains a name that you have seen in your mathematical mind.

### All will be revealed at the end of the performance.

### Ask one student to write a 3-digit number on the board.

### Ask a second student to turn this number around and subtract the smallest number from the largest number.

### Ask a third student to turn that number around and add the last two numbers.

### Example: N1 = 371.

### N2 = 173

### N1 – N2 = N3 = 371 – 173 = 198

### N4 = 891

### N4 – N3 = 891 + 198 = 1089

### Give a fourth student a phone book. Ask them to go to page 108 and count down 9 places on the first column and read out the name.

### Now open the envelope.

### Da! Da!

### How does it work? The numbers ALWAYS add up to 1089 so you had plenty of time to check out the name int he phone book.

### Source: Magic/Menatalism Tips and Tricks

## Trick 2: Luck Be a Math Nerd Tonight

November 30, 2012……………………………………………………………………………………

# Luck Be a Math Nerd Tonight

### Requirements: 1 die, a fanfare would be nice.

### You will find a fanfare here.

### Ask a student to roll the die, double the number and add 5. He can show the class the number, but not you.

### Ask the student to multiply this number by 5.

### Ask the student to roll the die again and add this number to the total.

### Now you can tell them the numbers they rolled.

### Example:

### N_{1} = 3

### Double: 2N_{1 }= 6

### Add 5: 2N_{1} + 5 = 11

### x5: 5(2N_{1} + 5) = 55

### Roll dice:

### N_{2} = 4

### Add 4:

### 55 + 4 = 59

### Math Nerd:

### Secretly subtracts 25 from this number:

### 59 – 25 = 34

### Da! Da! There are the two numbers rolled.

### Source: Magic/Menatalism Tips and Tricks

## Trick 3: Maths Swami Knows Your Birthday

November 30, 2012# .

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# Maths Swami Knows Your Birthday

### Requirements: Calculator and spooky demeanor

### Imagine your birthday was 24 September 1973.

### Written as an American date (not UK or Australia) this would be:

### 9-24-73.

### Give the calculator to a student:

### Take birthday month and add 18:

### 9 + 18 = 27

### x 25

### 27 x 25 = 675

### – 333

### 675 – 333 = 342

### x 8

### 342 x 8 = 2736

### – 554

### 2736 – 554 = 2182

### Divide by 2

### 2182/2 = 1091

### Add day of birthday date

### 1091 + 24 = 1115

### x5

### 1115 x 5 = 5575

### + 692

### 5575 + 692 = 6267

### x 20

### 6267 x 20 = 125340

### Add the last two digits only of your birth year

### 125340 + 73 = 125413

### – 32940

### 125413 – 32940 = 92473 = 9-24-73

### Yes! Yes!

### Hint: It probably would be easier to ask them for their birthday. Ha! But Maths Swami’s are mysterious beings.

### You will find a video link on Youtube

## Trick 4: Madame Mathematique Clairvoyant

November 30, 2012# .

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# Madame Mathematique Clairvoyant

### Requirements: Spooky music and spooky look.

### You will find some spooky music here.

### Ask a student to write down two 5-digit numbers. You rapidly write a 5-digit number underneath.

### Ask another student to write another 5-digit number. You write another 5-digit number quickly.

### Stand back.

### And instantly write the answer.

# Example:

### N_{1 }= 97413

### N_{2} = 28619

### N_{3} = 71380 (Each digit in N_{3} must add up to 9 with digits above)

### N_{4} = 64231

### N_{5} = 35768 (Each digit in N_{5} must add up to 9 with digits above)

### Now you will instantly write down the sum of these five numbers as

### 297411

### Da! DA!

### The trick is to subtract 2 from N_{1 }and put it in front:

### N_{1 }= 97413

### N_{1 }-2 = 97411

### Sum of 5 numbers = 297411

### Hint: Get as many students to add up the five 5-digit numbers on a calculator. You will beat them, but you will also need many answers as a number of students will key incorrect numbers.

# Magic Chat

## Trick 8: Spooky Maths Magic

November 30, 2012# .

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# Spooky Maths Magic

### Requirements; Smart board/data projector.

### This is mental maths, but not hard maths. You can play this video by Marco Frezza directly to the class.