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Maths Tricks

Multiplication and square tricks

Learn multiplication tricks and square tricks in math for fast calculation, here I have compiled some best tricks and shortcuts. In this post I have also explained shortcuts to find LCM and unit digit quickly.

Square tricks:

Square tricks for the numbers which are closer to 50  

Though I have written that this trick is for those number which are closer to 50, but still you can use this for all the numbers ranging between 1 to 100.

Case 1:
If the number is greater than 50.

For example, square the number 54.

Step 1: Write the 54 as addition of two numbers but one number must be 50.
54 can be written as (50+4)

Step 2: Here  4 is added on 50. Hence 4 square = 16 forms the digits at the extreme right.

Step 3:
Add 4 in 25 it comes out 29. So, they form the remaining digits.

So, the square of 54 is equal to 2916.
what are the best tricks in math for square of a number

Case 2: If the number is lesser than 50.

This square trick is almost same as previous one.
Let’s take the number 46.

Step 1: 46 can be written as (50-4)

Step 2: Here  4 is subtracted from 50. Hence 4 square = 16 forms the digits at the extreme right.

Step 3: Here subtracted number was 4, so subtract 4 from 25 it comes out 21. So, they form the remaining digits

So, the square of 46  is equal to 2116.
best math square tricks for fast calculation
Let’s take one more example that is 37

Learn top maths tricks and shortcuts in maths

Square trick for a number, which have unit digit equal to 5.
fast calculation for squaring a number whose unit digit is 5

Multiplication Tricks:

Trick 1: 

Multiplication trick for any two digit number:

Example: 63*42
Step 1: Multiply 6 with 4 it is equal to 24.
Step 2: Multiply 3 with 2 it is equal to 6
Best multiplication tricks for two digit numbers
Step 3: Now multiply 6 with 2 and 3 with 4 and add them.
6*2 + 3*4 = 24
multiplication tricks for two digit numbers

63 * 42 = 2646
So, with the help of this multiplication trick you can easily multiply two digit numbers.

Trick 2:

Another trick which I am explaining here, is very simple and interesting. For this multiplication trick, 2 conditions must be satisfied.

  1. The  sum of unit digit of both numbers must be 10.
    Example: 43*47, here the unit digit are 3 and 7, their sum is 10.
  2. The remaining digits must be same for both numbers.
    Example: 43 * 47, 112*118 etc.

43 * 47 =
Step 1: Multiply the digits at unit place, 3*7 = 21
Step 2: Multiply tens digit with next number, 4*5 = 20
So, the multiplication of 43 and 47 will be 2021.

Similarly, Let’s solve 112*118
Step 1: 8*2 = 16
Step 2: 11*12= 132
So, 112*118= 13216

Example 3: 91*99
Step 1: 9*1= 9
Just add an extra zero before 9 to make it a two digit number i.e. 09.
Step 2: 9*10 = 90
So, multiplication of 91 and 99 will be 9009.

Multiplication Trick 3:

Multiplication tricks for two numbers, which are in the range of 90 to 100.

Example: 95*96

multiplication tricks in maths to calculate fast

Shortcut to multiply a number to another number having only 9 as the digit.

Example: 999*232

Step 1: Subtract “1′ from 232
232 – 1 = 231

Step 2:  Subtract 232 from 999
999 – 231 = 768

So answer of 999 * 232 is 231768.

LCM Tricks

Before going into the short tricks, I recommend you first know the basic methods of LCM.

Step 1: Identify the largest number among the given numbers.

Step 2: Check whether the largest number is divisible by all other numbers, if it is divisible by all other numbers the largest number itself will be the LCM otherwise double the largest number and again check whether the number coming from doubling the largest number is divisible by all the numbers, if it is divisible by all other numbers that number will be the LCM otherwise triple the largest number and so on.

From step 1: Among 2, 4, 6, 8, 10, and 12 we know 12 is the largest number.

From step 2:

12 is not divisible by 8, 10.

12*2 = 24 , again 24 is not divisible by 10

12*3 = 36, again 36 is not divisible by 10

12*4 = 48, again 48 is not divisible by 10

12*5 = 60, again 60 is not divisible by 10

12*6 = 72, again 72 is not divisible by 10

12*7 = 84, again 84 is not divisible by 10

12*8 = 96, again 96 is not divisible by 10

12*9 = 108, again 108 is not divisible by 10

12*10 = 120, 120 is divisible by 10

So, 120 is the LCM of  2, 4, 6, 8, 10, and 12.

If you want to know division tricks you can know here.