Trick 1: The Great MATHoudini

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 in the phone book.

Source: Magic/Menatalism Tips and Tricks

Trick 2: The Math Teacher Knows

……………………………………………………………………………………

The Math Teacher Knows Everything

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:

N₁ = 3

Double: 2N₁ = 6

Add 5: 2N₁ + 5 = 11

x5:   5(2N₁ + 5) = 55

Roll dice:

N₂ = 4

Add 4:

55 + 4 = 59

The Math Teacher Knows:

Secretly subtracts 25 from this number:

59 – 25 = 34

Da! Da! There are the two numbers rolled.

Source: Magic/Menatalism Tips and Tricks

Oops! We forgot. Our 1st software Engineer was a Woman!

Margaret Hamilton joined the Apollo Project as NASA’s first computer programmer in 1965!!!

Not only was she the first person to use the term SOFTWARE ENGINEER, her computer programming skills saved the Apollo 11 space capsule from crashing during the 1969 landing on the moon.

She was presented with the PRESIDENTIAL MEDAL OF FREEDOM by President Obama in 2016.

 

Trick 3: Maths Swami Knows Your Age and Foot Size

Maths Swami 1: A Magic No.

Maths Swami 2: I Know 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

That Crazy Little Thing Called ZERO

Siri, what’s zero divided by zero?

Problems with Dividing by Zero

– Numberphile

Matthew Parker is an Australian stand-up comedian, author, YouTube personality and maths communicator.

Edible Zero. Really!

 

Trick 4: How to be a Mathematical Clairvoyant

How to be a Mathematical Clairvoyant

Requirements: Spooky music and spooky look.

You will find some spooky music here.

Tell your students you will beat them  adding up 5 x 5 digit numbers in your head when they are using calculators.

Method:

1. Ask a student to write down 2 x 5-digit numbers on the board.

2. You rapidly write a 5-digit number underneath.

3. Ask another student to write another 5-digit number.

4. You write another 5-digit number quickly.

5. You have 5 by 5 digit numbers. Say ‘Go’. You instantly write down the answer.

Stand back.

This is how it works:

N₁ = 97413

N₂ = 28619

N₃ = 71380  (Each digit in N₃ that you write down must add up to 9 with digits in No. above)

N₄ = 64231

N₅ = 35768  (Once again each digit in N₅ 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 N₁ and put it in front:

N₁ = 97413

N₁ -2 = 97411

Sum of 5 numbers = 297411

This is why it works:

Hint: When you get your students to add up the five 5-digit numbers on a calculator you will beat them, but they will also get many different answers as a number of students will key incorrect numbers.

Magic Chat

 

 

Trick 5: Cool Math Trick

Requirements: A Pack of Cards and a willing assistant.

Take 10 cards from pack including the 10 Diamonds.

Lay out card in 3 columns in a pattern of 4 down, 2 down, 4 down.

Put the 10 Diamonds at the top of the  left hand column.

Group students around. You turn your head away and ask a student to point to a card.

You carry on, think allowed and then ask your assistant to point to cards asking:

Is it this one?

No.

Is it this one?

No.…………………………………………………………………………………

When your assistant points to the 10 Diamonds he will show you the position using the diamonds. The cards are laid out on the table in the pattern of the diamonds on the 10 Diamonds.

Whenever your assistant asks is it this one? You will know.

See Mentalism Card Trick: