Want to make math more interesting for your child? Get ready for… 

Math Magic Tricks

Whether you are a parent or teacher trying to get children interested in math, showing them these tricks can help them become more engaged and curious about what else they can do with math.

Here are 19 simple but incredibly useful tricks to introduce to your students or children. 

Multiplying With 6
Take any even number and multiply it by 6. You will notice that the last digit of the product is the same as the number that was multiplied by 6. What’s even more remarkable is that the first digit (tens place) of the product will be half of the second digit (the ones place).
Example:
6 (×) 8 = 484 is half of 8
Adding Large Numbers
This is one of the most useful ways to add large numbers. In fact, it’s a fairly common technique in math curriculums globally. For those who are unfamiliar, the secret is to make each number a multiple of 10. 
Let’s dive right into an example.
Imagine you are trying to add 536 and 389. The sum is 925.
Introducing an easier, more magical way to add the two numbers together:
Round each number up to a multiple of 10

536 becomes 540, and 389 becomes 390

Add them together

540 + 390 = 930

Figure out how much you added to each number to round it up to a multiple of 10.
540 − 536 = 4 and 390 − 389 = 1

Add the results together

4 + 1 = 5

Subtract step 4 from step 2

930 − 5 = 925

The answer is 925.
Always Count on 7
This is a magic trick that never fails ⏤ the final answer is always 7.
Start by having your child select a number between 1 and 10

Let’s assume they picked the number 9

Add 5 to the number

9 + 5 = 14

Add 2 to the result

14 + 2 = 16

Subtract the number in step 1 (9)

16 − 9 = 7

The answer is always 7. 
Guessing Age & Shoe Size
You easily guess any child’s age using the following simple math magic trick:
Have them write their age on a piece of paper

Let’s say the child wrote down 11

Multiply it by 20

11 (×) 20 = 220

Add today’s date (if it is the 23rd day of the month, the number should be 23)

220 + 23 = 243

Multiply the result by 5

243 (×) 5 = 1215

Tell them to add their shoe size to the result (for example, the child’s shoe size is 6)

1215 + 6 = 1,221

Multiply today’s date 5 times and subtract it from the result

1221 − (23 (×) 5) = 1,220 − 115 = 1,106

The first two digits are the child’s age (11) and the remaining two digits are their shoe size (06) – 1,106. 
Now that is magical! 
The Answer is 15
Here’s another amazing math trick that never fails to dazzle. 
Pick any whole number

For example, 13

Multiply it by 3

13 (×) 3 = 39

Add 45

39 + 45 = 84

Double the result

84 (×) 2 = 168

Divide the result by 6

168 / 6 = 28

Subtract the original number from the result

28 − 13 = 15

The answer is 15.
The Answer is 37
This next math trick will blow your child’s mind:
Think of a three-digit number that has the same sequence of numbers as 555, 888, etc.

Today, let’s pick 333

Add up the three digits

3 + 3 + 3 = 9

Divide the sum into the original number

333 / 9 = 37

The answer will always be 37.
The Answer is 8
Here’s a neat math magic trick that will have your child returning to the number 8:

Pick a two-digit number 
45
Subtract 1 from the number

45 – 1 = 44

Multiply the difference by 3

44 (×) 3 = 132

Add 12 to the product
132 + 12 = 144

Divide the sum by 3

144 / 3 = 48

Add 5 to the quotient

48 + 5 = 53

Subtract the original number from the sum
53 − 45 = 8
Hence, the answer will always be the number 8.
The 11 Rule
There are many multiplication math magic tricks, but this one will allow your child to multiply any two-digit number with 11. 

Think of any two-digit number

For example, 21

Add the two individual digits together

2 + 1 = 3

Place the sum between the two digits of your original number:

Original number = 21. Sum = 3
Final answer = 231 
The byproduct of 21 and 11 is indeed 231.
Bonus 11 Rule! 
What if the sum of the original numbers equals a 2-digit number? Then what do you do? Read more to find out.
Let’s take another example. If the original number = 68, then the sum of 6+8=14. 14 is a two-digit number. (What you DON’T do is place the 14 between 6 and 8 like this ⏤ 6148.) Instead, what you do is “carry the one” to the hundredth place. 
  6  – 8+1 4 –     7 4 8
And just to make sure the rule of 11 still works, the byproduct of 68 (×) 11 = 748
Multiplying Large Numbers
We’ve found a way to teach children how to quickly multiply large numbers. 
However, this one only works if one of the numbers is even. For this example, we’re going to use 20 (×) 700.
Follow the steps below:
Divide the even number in half

20 / 2 = 10

Double the second number

700 (×) 2 = 1,400

Multiply the results from step 1 and step 2

10 (×) 1,400 = 14,000

The answer to 20 (×) 700 is 14,000.
Math Magic
Memorizing Pi
Are your children having trouble remembering the first seven digits of the number Pi? 
Ask them to write down “How I wish I could calculate Pi” and count the letters in each word. 
The result will be 3.141592.
Always the Same Two-digit Single Numbers
In this simple trick, you will always end up with the same two-digit numbers.
Start by thinking of any two-digit number

We’ll use 19 for this example

Double one of the digits

1 (×) 2 = 2

Add 5 to the product

2 + 5 = 7
Multiply the product by 5

7 (×) 5 = 35
Add the other number to the product
35 + 9 = 44
Subtract 4 from the sum
44 − 4 = 40
Subtract 21 from the difference
41 − 21 = 19
Notice you have the exact two-digit number you started with! Isn’t that cool?!
Contains the Digits 1, 2, 4, 5, 7, 8
Following the steps below will result in a number that contains the digits 1, 2, 4, 5, 7, 8:
Pick a number between 1 and 6
Let’s assume you picked 3
Multiply the number by 9
3 (×) 9 = 27
Multiply the product by 111
27 (×) 111 = 2997
Multiply that product by 1001
2997 (×) 1,001 = 2,999,997
Divide the product by 7
2,999,997 / 7 = 428,571
As you can see, the answer contains the digits 1, 2, 4, 5, 7, 8.
The Answer is 2
Here’s a cool magical math trick where the answer is always going to be 2:
Pick any number

Let’s assume it is 9

Multiply it by 3

9 (×) 3 = 27

Add the result by 6

27 + 6 = 33

Divide the result by 3

33 / 3 = 11

Subtract the result from the original number

11 − 9 = 2

These steps will always return to 2.
The Answer is 1,089
We’ve seen math magic tricks that get us 2, 7, 8, 15, and 37 consistently, but what about a large number like 1,089? 
Follow the steps below:
Think of any three-digit number
For example, 482
Arrange the digits from highest to lowest
842
Subtract the result by the number in reverse
842 − 248 = 594
Reverse the number that is the difference 
The reverse of 594 is 495
Then add that number to the result
594 + 495 = 1,089
Amazingly, you get 1,089 every single time. Try it with other three-digit numbers.
Multiplying Multiples of 5 in Your Head
This trick allows you to mentally calculate multiples of 5. The secret is realizing that 5 is half of 10. 
Here’s how it works:
Multiply the number you’re trying to multiply by 5 with by 10

For example, if you try to multiply 24 by 5, you would first multiple 24 by 10, which is 240. That is easy, right?!

Divide the product by 2

240 / 2 = 120

As you can see, the answer is 120, which is what you get when you multiply 24 by 5.
Creating the 9 Times Tables With Your Fingers
Learning the multiples of 9 can be tons of fun for your child, especially if they use their fingers. 
Here’s how:
Extend both your arms and fingers in front of you with your palms facing down ⏤ starting from the left, each finger is a number from 1 to 10 If, for example, you want to multiply 4 (×) 9, you would fold the fourth (pointer) finger downCount the fingers on each side of the folded finger.

There will be 3 on the left and 6 on the right side of the folded finger
This means the answer is 36. It works every time!
Subtracting From 1,000
You can teach children to subtract large numbers from 1000 quite simply. 
Let’s use 1000 − 645 as an example:
Subtract each digit from 9 apart from the digit in the ones place.
9 − 6 = 3 and 9 − 4 = 5

Always subtract the digit in the ones place from 10

10 − 5 = 5

Put the results together to find the answer

355

This means 1,000 − 645 = 355.
A Magic Way to Find a Percentage
Trying to find 30% of 500? Here’s an easy way to do it:
Divide both numbers 10

30 / 10 = 3 and 500 / 10 = 50

Multiply the two quotients

3 (×) 50 = 150

 30% of 500 is 150. That is pretty cool!
Multiplication by 4
Here’s a trick to quickly multiply numbers by 4:
If you have this problem: ___  (×)  4 = ___.  For example 8 (×) 4 = ___ Take the number you’re multiplying by 4 and double it

For example, If the number is 8, then 8 (×) 2 = 16 or 8 + 8 = 16

Double that sum again to find the answer

16 + 16 = 36 
Therefore, 8 (×) 4 = 36
Math magic tricks are a fun way to show children how to do math equations quickly and easily. By turning math into a game, you’ll teach your child to practice and think about math as fun! They will be dying to test out these tricks for themselves with other numbers to see if they really work! The beauty is that these tricks can make even your most math-reluctant children and students math-curious.

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