15 Math Tricks for kids

January 18, 2021 Reading Time: 6 minutes 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…

January 18, 2021

Reading Time: 6 minutes

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.

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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!

6 x 4 = 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.

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.

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.

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.

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.

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.

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. 

The number 6 yields the answer 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.

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.

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.

 

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

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.

13. Multiplying 5 times any number

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

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

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

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.

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.

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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External References

To know more about Math tricks, please visit these blogs:

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NCERT Solutions for Class 7 Maths Chapter 12

NCERT Solutions for Class 7 Maths Chapter 12Class 7 Maths Chapter 12 all Exercises SolutionClass: 7Maths (English and Hindi Medium)Chapter 12:Algebraic Expressions7 Maths Chapter 12 SolutionsClass 7 Maths Chapter 12 Algebraic Expressions all four exercises solutions are given below. These are updated NCERT Solutions for 2021-2022 for the new session 2021-22. 7 Maths Chapter 12…

NCERT Solutions for Class 7 Maths Chapter 12

Class 7 Maths Chapter 12 all Exercises Solution

Class: 7Maths (English and Hindi Medium)
Chapter 12:Algebraic Expressions

7 Maths Chapter 12 Solutions

Class 7 Maths Chapter 12 Algebraic Expressions all four exercises solutions are given below. These are updated NCERT Solutions for 2021-2022 for the new session 2021-22.

  • 7 Maths Chapter 12 All Exercises in English Medium

  • 7 Maths Chapter 12 All Exercises in Hindi Medium

Class 7 Maths Exercise 12.1 and Exercise 12.2 Solution in Video

Class 7 Maths Exercise 12.1 Solution in VideoClass 7 Maths Exercise 12.2 Solution in Video

Class 7 Maths Exercise 12.3 and Exercise 12.4 Solution in Video

Class 7 Maths Exercise 12.3 Solution in VideoClass 7 Maths Exercise 12.4 Solution in Video

About NCERT Solutions for Class 7 Maths Chapter 12

In 7 Maths Chapter 12 Algebraic Expressions, the questions based on mainly algebraic identities and it applications. In this chapter we will study about a variable and a constant. A variable can take various values. Its value is not fixed. On the other hand, a constant has a fixed value. Examples of constants are: 4, 20, –127, etc. Before discussing the algebraic expression, we should know about the terms, coefficients, etc.
Basic Terms about Algebraic Expressions
1. Term: The parts of algebraic expressions which are formed separately and then added for form an algebraic 2. expressions. Such parts of an expression which are formed separately first and then added are known as terms.
Coefficient: The factors of the terms may be numerical and the others algebraic. The numerical factor is said to be the numerical coefficient or simply the coefficient of the term.
In this chapter we will learn the addition or subtractions of expression on the basis of like terms or unlike terms. Terms like monomial, binomial, trinomial or any polynomial. Finding the value of an expression given in this chapter will help you in later classes to study functions of variables.

Feedback & Suggestions

All the changes that we have made as the suggestions of the students, if someone is facing difficulty with these changes, please inform us. For more suggestions, you are welcome. We are improving our solutions 2021-22 and contents day by day with the help of your help.

Important Questions on Class 7 Maths Chapter 12

If m = 2, find the value of m – 2.

Putting the value of m in m – 2 We have 2 – 2 = 0

What do you mean by like terms in Algebraic Expressions?

The terms having the same algebraic factors are called like terms.

What are unlike terms in Algebraic Expressions?

The terms having different algebraic factors are called unlike terms.

What are monomial, binomial or trinomial in Algebraic Expressions?

Expression with one term is called a ‘Monomial’.
Expression with two unlike terms is called a ‘Binomial’.
Expression with three unlike terms is called a ‘Trinomial’.

How are the mathematical operations done in algebraic expressions?

When we add (or subtract) two algebraic expressions, the like terms are added (or subtracted) and the unlike terms are written as they are.

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NCERT Solutions for Class 10 Maths Chapter 8

Class 10 Maths Chapter 8 Introduction to Trigonometry SolutionClass 10 Maths Chapter 8 all Exercises Solution10th Maths Chapter 8 Exercise 8.110th Maths Chapter 8 Exercise 8.210th Maths Chapter 8 Exercise 8.310th Maths Chapter 8 Exercise 8.4Class: 10MathematicsChapter 8:Introduction to TrigonometryContents:NCERT Solutions in Hindi and English Class 10 Maths Chapter 8 Exercise 8.1 Solution in Hindi…

Class 10 Maths Chapter 8 Introduction to Trigonometry Solution

Class 10 Maths Chapter 8 all Exercises Solution

  • 10th Maths Chapter 8 Exercise 8.1

  • 10th Maths Chapter 8 Exercise 8.2

  • 10th Maths Chapter 8 Exercise 8.3

  • 10th Maths Chapter 8 Exercise 8.4

Class: 10Mathematics
Chapter 8:Introduction to Trigonometry
Contents:NCERT Solutions in Hindi and English

Class 10 Maths Chapter 8 Exercise 8.1 Solution in Hindi Video

Class 10 Maths Exercise 8.1 Solution in Video

Class 10 Maths Exercise 8.1 ExplanationClass 10 Maths Chapter 8 Exercise 8.1 Solution

10th Maths Chapter 8 Solutions

NCERT Solutions for class 10 Maths Chapter 8 Introduction to Trigonometry exercises from 8.1 to 8.4 are given to use online of download in PDF format free. These solutions are in Hindi and English Medium format. If you have any doubt, please visit to Discussion Forum to ask your doubts.

Class 10 Maths Chapter 8 Exercise 8.2 Solution in Hindi Video

Class 10 Maths Exercise 8.2 Solution in Video

Class 10 Maths Exercise 8.2 ExplanationClass 10 Maths Chapter 8 Exercise 8.2 Solution

Class 10 Maths Chapter 8 Exercise 8.3 Solution in Hindi Video

Class 10 Maths Exercise 8.3 Solution in Video

Class 10 Maths Exercise 8.3 ExplanationClass 10 Maths Chapter 8 Exercise 8.3 Solution

Class 10 Maths Chapter 8 Exercise 8.4 Solution in Hindi Video

Class 10 Maths Exercise 8.4 Solution in Video

Class 10 Maths Exercise 8.4 ExplanationClass 10 Maths Chapter 8 Exercise 8.4 Solution

NCERT Solutions for Class 10 Maths Chapter 8

Historical Facts!

1. The creator of trigonometry is said to have been the Greek Mathematician Hipparchus of the 2nd century BC.
2. The word Trigonometry which means triangle measurement is credited to Bastholoman Pitiscus (1561-1613).
3. The first use of the idea of ‘sine’ can be found in the work of ‘Aryabhatiyam’ of Aryabhata in 500 AD. Aryabhata used the word Ardha-jya for the half-chord, which was shortened to Jya or Jiva in due course. When the Aryabhatiyam was translated into Arabic, the word Jiva was retained. It was further translated into ‘Sinus’, which means curve in Latin. The word ‘Sinus’ also used as sine was first abbreviated and used as ‘sin’ by an English professor of astronomy Edmund Gunter (1581-1626).
4. The origin of the terms ‘Cosine’ and ‘tangent’ was much later. The cosine function arose from the need to compute the sine of the complementary angle. Aryabhata called it Kotijya. The name cosinus originated with Edmund Gunter. In 1674, another English mathematician Sir Jonas Moore first used the abbreviated notation ‘cos’.

Complementary angles relationship in trigonometric ratios

Trigonometry - FormulaeTrigonometry - Formulae

Trigonometric Identities

Trigonometry - Trigonometric IdentitiesTrigonometry - Trigonometric Identities

Trigonometric Ratios

Trigonometry - Trigonometric RatiosTrigonometry - Trigonometric Ratios

How many exercise wise questions are there in class 10 Maths chapter 8?

There are 4 exercises in class 10 math chapter 8 Introduction to Trigonometry.
In first exercise (Ex 8.1), there are in all 11 questions.
In second exercise (Ex 8.2), there are in all 4 questions.
In third exercise (Ex 8.3), there are 7 questions.
In fourth exercise (Ex 8.4), there are 5 questions.
So, there are in all 27 questions in class 10 math chapter 8 Introduction to Trigonometry.
There are in all 15 examples in class 10 math chapter 8 Introduction to Trigonometry.
Examples 1, 2, 3, 4, 5 are based on Ex 8.1.
Examples 6, 7, 8 are based on Ex 8.2.
Examples 9, 10, 11 are based on Ex 8.3.
Examples 12, 13, 14, 15 are based on Ex 8.4.

What are the important examples from chapter 8 class 10 math?

Examples given in NCERT books are always important for CBSE exams. Examples 3, 4, 5, 7, 8, 10, 11, 13, 14 and 15 of chapter 8 (Introduction to Trigonometry) of class 10 math are the important examples from exam point of view. In exam questions can come from these examples.

Which are the main topics students go through in chapter 8 of class 10th Mathematics?

In chapter 8 Introduction to Trigonometry of class 10th math, Students will study:
1) Trigonometric Ratios.
2) Trigonometric Ratios of Some Specific Angles.
3) Trigonometric Ratios of Complementary Angles.
4) Trigonometric Identities.
This chapter is very interesting. Also this chapter is completely new for students.

Why is chapter 8 of Class 10th Maths important?

Chapter 8 (Introduction to Trigonometry) of 10th Math is important because there is a chapter in class 11th math named Trigonometric functions and chapter 8 (Introduction to Trigonometry) of 10th Math works as a base for that chapter. Also from exam point of view chapter 8 (Introduction to Trigonometry) of 10th Math is very important. Every year 7-8 marks questions come from this chapter.

What do you learn about Trigonometry in Class 10 Maths Chapter 8?

Trigonometry is the oldest branch of mathematics. This concept was first used by Aryabhata in Aryabhatiyam in 500 A.D. Trigonometry is a word consisting of three Greek words: Tri-Gon-Metron. ‘Tri’ means three, ‘Gon’ means side and ‘Metron’ means measure. So, trigonometry is the study related to the measure of sides and angles of a triangle in particular, right triangles (in CBSE class 10).

How can I score more that 90% in class 10 Maths Chpater 8 Trigonometry?

To score well in trigonometry, we should practice hard the entire chapter 8 in 10th Maths. Specially exercise 8.4 needs more time to spend for solving the questions based on identities. All the parts of question 5 of exercise 8.4 asked in exams frequently.

Is there any application of trigo as a tool in astronomy for Class 10 Mathematics 8th Chapter?

Trigonometry is used in astronomy to determine the position and the path of celestial objects. Astronomers use it to find the distance of the stars and planets from the Earth. Captain of a ship uses it to find the direction and the distance of islands and light houses from the sea. Surveyors use to map the new lands.

What is the objective of Chapter 8 in Class 10 Maths Trigonometry?

Objective of Class 10 Trigonometry:
Identifying the opposite side, adjacent side and hypotenuse of right triangle with respect to given angle A. Defining the six rations (sine, cosine, tangent, secant. cosecant and cotangent) related to the sides of a right angled triangle. Finding the values of trigonometric rations of a given right angled triangle. Finding the values of trigonometry rations of some standard angles (0, 30, 45, 60 and 90) in degrees. Using complementary angles and applying it into trigonometric identities to prove another identities.

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