Short Maths Tricks

Rating:
0
(0)
Maths Short Tricks

Be it for simple mathematical operations or for complex problems, we often use calculators. This, in turn, has made us more dependent on its use. To overcome such dependence and to enhance the mental ability to solve mathematical equations with ease, getting adept in short and simple tricks is essential. By practising these tricks, not only will you be able to do lots of mental maths on your own but will also save crucial time while giving scholastic or competitive exams. So, in this blog, we have shared some super easy maths short tricks! 

Top 10 Short Maths Tricks 

Let’s hop onto some quick maths short tricks which will help you ace those complex problems in mental maths tests and quizzes!

1. Multiplication Short Tricks

Often, multiplying two-digit numbers is difficult. Hence, through this maths short trick, you will be able to multiply fast and in an easy way. 

Let us consider two numbers, 16 and 77 
What would be the solution of 16 x 77?

In this trick, we will begin by picking up the first number. 
16 is an even number, divide it in half and we get, 16/ 2 = 8 
Now, double the second number i.e., 77 x 2 = 154 

For your final answer, you can simply multiply the resultant numbers i.e., 
154x 8 = 1232

2. Multiplying any Two-digits Which Have Same Tens Digits 

Through this trick, we will learn to multiply numbers where the ten’s digit is the same and the one’s digit adds up to 10.

Q. Find the answer of 42 x 49

Take the ten’s digit and multiply it by the next highest number, i.e, 4 X 5= 30.
Next, multiply both the one’s digit. 2 x 8 = 16.
Lets put together both the digits and the answer will be 3016. 

3. Division Tricks

Out of all the maths short tricks, this one will help you solve the division problems in a jiffy! 

To Check Divisibility by 9

If the total sum of all the digits of a number is divisible by 9, then the number is divisible by 9. 
For Example: 4387=  4 + 3+ 8+ 7 =22
As 22 is not divisible by 9 which means that 4387 is not divisible by 9 as well. 

To Check Divisibility by 4

To determine whether a number is divisible by 4 or not, we have to analyse its last 2 digits. If they are divisible by 4, the entire number will be divisible by 4. 

For Example: Let us consider 7864, the last 2 digits of this number make the number 64 which is divisible by 4, hence, 7864 is divisible by 4.

4. Maths Short Tricks to Find Percentage

We all struggle to find percentages of complex numbers but don’t worry, one of the most useful maths short trick is this one. 

Let us imagine the number 685 and we have to calculate 5% of it. So, what we have to do is,
The digit 685 will have decimal like 685.0 
Let us move the decimal one place forward, the number becomes 68.5

Now, we have to divide the number 68.5 by 2 
We get, 34.25 
Thus, 5% of 685 is 34.25 

5. Square Short Trick

Amongst all the maths short tricks, this one can be applied to calculating the square of numbers ending with 5 as it is a daunting task to calculate such numbers.

Let us consider the number 85
For finding its square, we will begin by squaring the units number which is 5.

We get the answer as 25 and this number will be the last two digits of your answer.
A part of the answer would thus be _  _ 25.

Now, you will have to multiply the ten’s digit number with its very next digit. 
So, 8 x 9= 72.
No 72 becomes your prefix and the final answer is 7225

6. Maths Short Trick for Square Root Short Trick

This tricks will help you solve square root problems in the wink of an eye:

Square Root of a Four-Digit Number

Let’s find the square root of a four digit number with an example:

Let’s take a look at 3364.

Pick up the last two digits first. Here it is 64. 
Since the unit digit is 4, we can say that the unit digit of the square root will either be 2 or 8.

Now, let’s pick up the first two digits. Here it is 33
Since 33 comes between the square of 5 and 6, i.e. 25<33<36, we can say the tens’ digit of the square root of 3364 will be 5. 

So, now we have two options, 52 or 58.
Now to choose between the two, multiply the tens and ones digit of both the options 52 and 58 and compare them with 33 (the thousand and hundred position of the digit).

5*2= 10
5*8=40
The product should be more than or equal to 33.
Since 10<33, the answer has to be 58.
The Square root of 3364 is 58.

7. Cube Root Short Trick

Let’s learn the cube root short trick by this example:

Let’s take  39304.

First, pick up the last digit of the cube. Here it is 4. If the last digit is 4, the cube root’s last digit will be 4.

It is important to note in general that:

  • If the last digit of a cube root is 8 then the unit digit will be 2.
  • If the last digit of a cube root is 2 then the unit digit will be 8.
  • If the last digit of a cube root is 3 then the unit digit will be 7.
  • If the last digit of a cube root is 7 then the unit digit will be 3.
  • If the last digit of a cube root is other than 2, 3, 7 and 8 then put the same number as the unit digit.

Going back to the cube root, we know the unit place for the cube root is 4. Now, ignoring the last three digits of the number, pick up the rest. Here, it is 39.

Check the closest cubes to 39. The closest cube to 39 is 27(Cube of 3) and 64 (cube of 4). Now, since 27 is closer to 39 than 64, the first digit will be 3.

So, the cube root of 39304 will be 34.

8. Quadratic Equations

Let’s learn a simple way to solve quadratic equations with an example.

Let’s take  x² – 18x + 45 = 0

Multiply the coefficient of x²  with 45. Here it is 1*45=45

Multiply -1 with the coefficient of x. Here it will be -1* (-18)=18

Now, the two values will be on the basis of the digits that add up to become 18 and the same digits when multiplied produce 45.

So, here the answer is 15 and 3. The signs will depend on whether 18 and 45 are positive or not. If both are positive, the answers will be positive, if even one is negative, the answer will be negative.

9. How to Multiply Numbers that End with Zero

Multiplying numbers that end with zero is simple. All you need to do is multiply the numbers and add the rest of the zeros. For example:

500 * 200

Multiply 5 and 2
5*2=10

Now, Put all the zeros at the back of 10. Since the numbers had 4 zeros (500 and 200), add 4 more zeros making it 100000

So, 500*200=1,00,000

10. Subtracting from 1000

The basic rule of solving this is subtracting each number with 9 except the last one. This can also be followed for other multiples of 10 like 10,000 or others.

For eg: 572

For this, you need to:

Subtract 5 from 9= 4
Subtract 7 from 9=2

Subtract 2 from 10=8

So, the answer will be 428.

1000-572=428

Importance of Learning Short Maths Tricks

Be it a professional career or for preparing Maths for competitive exams, easy maths short tricks play a vital role in enhancing your ability to solve complex arithmetic problems in an easy and time-saving manner. The techniques break down the large problems in smaller ones so there is minimal time required to solve them. Here are some of the major features of applying maths short tricks:

  • Learning math tricks enhances your thinking abilities and problem-solving skills. 
  • Practically, in almost every career path, math in some way or the other is applied. So, it becomes a total win-win situation!
  • In order to establish a flourishing career in Mathematics, these small tricks will be of great help.

Thus, we hope that through this blog, you can now solve various questions using maths short tricks. These tricks are extremely helpful if you are preparing for any competitive examinations like SAT, GMAT, GRE, etc. Hence, we at Leverage Edu, provide engaging online coaching for exams like SAT, GRE, GMAT, etc where you can learn ample other helpful tricks. Hurry up! Book a free demo session now!

Leave a Reply

Your email address will not be published. Required fields are marked *

10,000+ students realised their study abroad dream with us. Take the first step today.
+91
Talk to an expert for FREE

You May Also Like

BODMAS Questions
Read More

BODMAS Questions

BODMAS stands for Bracket, Of, Division, Multiplication, Addition and Subtraction. The BODMAS is used to explain the order of…