Math & Beyond

15 Math Tricks that will Blow your Mind!

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January 18, 2021

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Introduction

Not everyone is a master at juggling numbers, but the subject isn't as complicated as it seems if you make use of simple maths tricks that will make solving any math problem a piece of cake! 

To understand maths easily, the subject can be seen as a game of building blocks stacked on one another — the base must have a strong foundation to move into more complex concepts and tough applications.

A lot of students, as well as a lot of parents, are intimidated by math problems, especially if they involve large numbers and complicated calculations.

Math tricks help you learn techniques on how to solve questions quickly and can help students develop greater confidence in math, improve math skills and understanding.

15 Math Tricks that will Blow your Mind-PDF

Here are some simple math tricks that can help you perform calculations more quickly and easily. Math tricks help you learn techniques on how to solve questions quickly and can help students develop greater confidence in math. Here is a downloadable PDF to explore more.

📥 15 Math Tricks that will Blow your Mind-PDF

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Math tricks

It is also important to consider how the concepts of maths are interconnected. What you learn about multiplication can be applied to division, which also applies to factors and multiples, which can be used to understand fractions. Mathematics tricks help find such connections between concepts and help you speed up calculations.

Maths tricks, when learned at an early age works like magic and helps students excel at academics as well as advanced courses opening up an array of opportunities for the future.

Also read:


15 Math Tricks for kids

1. Multiplying by 6 

If you multiply 6 by an even number, the answer will end with the same digit. The number in the ten's place will be half of the number in the one's place.This ploy works effortlessly and students can add it to their collection of maths magic tricks!

Example

6 x 4 = 24

24

 2. The Answer Is 2

Think of a number.
Multiply it by 3.
Add 6.
Divide this number by 3.
Subtract the number from Step 1 from the answer in Step 4.
The answer is 2.

2

3. Same Three-Digit Number

Think of any three-digit number in which each of the digits is the same. Examples include 333, 666, 777, and 999.
Add up the digits.
Divide the three-digit number by the answer in Step 2.
The answer is 37.

37

4. Six Digits Become Three

Take any three-digit number and write it twice to make a six-digit number. Examples include 371371 or 552552.
Divide the number by 7.
Divide it by 11.
Divide it by 13.
The order in which you do the division is unimportant!
The answer is the three-digit number.

Example

371371 gives you 371 or 552552 gives you 552.
A related trick is to take any three-digit number.
Multiply it by 7, 11, and 13.
The result will be a six-digit number that repeats the three-digit number.

456 becomes 456456

5. The 11 Rule

The 11 rule is one of those magic tricks and methods that can be used to quickly multiply two-digit numbers by 11 in your head.
Separate the two digits in your mind.
Add the two digits together.
Place the number from Step 2 between the two digits. If the number from Step 2 is greater than 9, put the one's digit in the space and carry the ten's digit.

Example

72 x 11 = 792.
57 x 11 = 5 _ 7, but 5 + 7 = 12, so put 2 in the space and add the 1 to the 5 to get 627

6. Memorizing Pi

This is probably the most fun tricks in maths -to remember the first seven digits of pi, count the number of letters in each word of the sentence:
"How I wish I could calculate pi."
This becomes 3.141592.

3.141592

7. Contains the Digits 1, 2, 4, 5, 7, 8

Select a number from 1 to 6.
Multiply the number by 9.
Multiply it by 111.
Multiply it by 1001.
Divide the answer by 7.
The number will contain the digits 1, 2, 4, 5, 7, and 8. 

Example

The number 6 yields the answer 714285.

714285

8. Multiply Large Numbers in Your Head

Another math magic tricks and methods to apply to easily multiply two double-digit numbers, is to use their distance from 100 to simplify the math:
Subtract each number from 100.
Add these values together.
100 minus this number is the first part of the answer.
Multiply the digits from Step 1 to get the second part of the answer.

9. Super Simple Divisibility Rules

You've got 210 pieces of pizza and want to know whether or not you can split them evenly within your group. Rather than taking out the calculator, use these simple shortcuts to do the math in your head:
Divisible by 2 if the last digit is a multiple of 2 (210).
Divisible by 3 if the sum of the digits is divisible by 3 (522 because the digits add up to 9, which is divisible by 3).
Divisible by 4 if the last two digits are divisible by 4 (2540 because 40 is divisible by 4).
Divisible by 5 if the last digit is 0 or 5 (9905).
Divisible by 6 if it passes the rules for both 2 and 3 (408).
Divisible by 9 if the sum of the digits is divisible by 9 (6390 since 6 + 3 + 9 + 0 = 18, which is divisible by 9).
Divisible by 10 if the number ends in a 0 (8910).
Divisible by 12 if the rules for divisibility by 3 and 4 apply.

Example

The 210 slices of pizza may be evenly distributed into groups of 2, 3, 6, 10.

10. Finger Multiplication Tables

Everyone knows you can count on your fingers. Did you realize you can use them for multiplication? A simple maths magic trick to do the "9" multiplication table is to place both hands in front of you with fingers and thumbs extended. To multiply 9 by a number, fold down that number finger, counting from the left.

Example 1

To multiply 9 by 5, fold down the fifth finger from the left. Count fingers on either side of the "fold" to get the answer. In this case, the answer is 45.

45

 

Example 2

To multiply 9 times 6, fold down the sixth finger, giving an answer of 54.

54

11. Adding large numbers

Adding large numbers just in your head can be difficult. This method shows how to simplify this process by making all the numbers a multiple of 10. Here is an example:
644 + 238
While these numbers are hard to contend with, rounding them up will make them more manageable. So, 644 becomes 650 and 238 becomes 240.
Now, add 650 and 240 together. The total is 890. To find the answer to the original equation, it must be determined how much we added to the numbers to round them up.
650 – 644 = 6 and 240 – 238 = 2
Now, add 6 and 2 together for a total of 8
To find the answer to the original equation, 8 must be subtracted from the 890.
890 – 8 = 882
So the answer to 644 +238 is 882.

882

12. Subtracting from 1,000

Here’s a basic rule to subtract a large number from 1,000: Subtract every number except the last from 9 and subtract the final number from 10
For example:
1,000 – 556
Step 1: Subtract 5 from 9 = 4
Step 2: Subtract 5 from 9 = 4
Step 3: Subtract 6 from 10 = 4
The answer is 444.

444

13. Multiplying 5 times any number

When multiplying the number 5 by an even number, there is a quick way to find the answer.

Example 1

For example, 5 x 4 =
Step 1: Take the number being multiplied by 5 and cut it in half, this makes the number 4 become the number 2.
Step 2: Add a zero to the number to find the answer. In this case, the answer is 20.
5 x 4 = 20

20
Example 2

When multiplying an odd number times 5, the formula is a bit different.
For instance, consider 5 x 3.
Step 1: Subtract one from the number being multiplied by 5, in this instance the number 3 becomes the number 2.
Step 2: Now halve the number 2, which makes it the number 1. Make 5 the last digit. The number produced is 15, which is the answer.
5 x 3 = 15

15

14. Division tricks

Here’s a quick trick in maths to know when a number can be evenly divided by these certain numbers:
10 if the number ends in 0
9 when the digits are added together and the total is evenly divisible by 9
8 if the last three digits are evenly divisible by 8 or are 000
6 if it is an even number and when the digits are added together the answer is evenly divisible by 3
5 if it ends in a 0 or 5
4 if it ends in 00 or a two digit number that is evenly divisible by 4
3 when the digits are added together and the result is evenly divisible by the number 3
2 if it ends in 0, 2, 4, 6, or 8

15. Tough multiplication

When multiplying large numbers, if one of the numbers is even, divide the first number in half, and then double the second number. This method will solve the problem quickly.

Example 

For instance, consider 20 x 120
Step 1: Divide the 20 by 2, which equals 10. Double 120, which equals 240.
Then multiply your two answers together.
10 x 240 = 2400
The answer to 20 x 120 is 2,400.

2400

Conclusion 

Mathematics tricks are a great way to make math fun! Your child will be able to do complex calculations without the aid of a calculator using their mental capabilities.

With regular practice, students will quickly get a hang of these mental math tricks to do speed math. Math tricks are extremely educative and will make your children extremely confident with numbers like never before!


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