Easy Multiplication of 5 digit numbers

Multiplication of two five digit numbers

Suppose we have to multiply two 5 digit numbers like

   3 5 4 1 2

x 2 6 3 4 1

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Easy Calculation

Division of any big number ending in five by any two digit number ending in five can be done with just mind calculation if you use the following technique:

Suppose let us take the example 1625 divided by 35

Multiplying Consecutive Numbers

Suppose we have to multiply two consecutive numbers say n and n+1

then n x (n+1) = n² + n

If we take it in the reverse way, say (n-1) and n

then (n-1) x n = n² – n

We can apply this for speed calculation,

Fun Numbers Part 3

One in numbers make it fun for its operations. Multiply one with any number the result will be the number itself same for the operation division also.. Let us check some operations with 1.

Cube of 3 digit numbers

Cube of 3 digit number

One easy method to find the cube of a 3 digit number.  let me put an example 462 ³

Squaring 3 digit numbers ending in 1

There is a short cut method for squaring 3 digit numbers ending in 1 rather than going for normal multiplication. If you can practice a bit with this method then you can square such numbers in mind itself. Let me explain the method with an example.

Squaring of 3 digit numbers ending in 5

Let me explain the easier method for squaring 3 digit numbers ending in 5 with an example:

Fun Numbers Part 2

37 is another fun number. 37 is a prime number and reversing the number 73 is also a prime number. If you multiply 37 with multiples of 3 see:

Fun Numbers Part 1

A number is a mathematical object used to count and measure. A notational symbol that represents a number is called a numeral but in common use, the word number can mean the abstract object, the symbol, or the word for the number. There are certain numbers, when used for some operations gives interesting results. It is fun exploring such numbers. If these interesting numbers are kept in our memory it makes calculation easy for many problems

MIND MULTIPLICATION of numbers close to 100

Here is a simpler method to find the product of 2 numbers  close to 100 by just mind calculation

Example 1 : Suppose you want to know 98 x 99

Step 1 :98 is 2 short of 100 so put2 below 98

     98 x 99
      2
Step 2: 99 is 1 short of 100  so put 1 below 99

    98 x 99
     2     1
Step 3: Multiply the 2 numbers put below
  2 x 1 = 2  this will so 02 will be the last part of the answer

Step 4: Subtract diagonally
     98-1 =97
    99 -2 =97
     this would be the first part of the answer so

98 x 99 =9702

Example 2 : 95 x 98

step 1 : 95 x 98
            5
step 2 : 95 x 98
            5      2
step 3 : 5 x 2 = 10

step 4 : 95 - 2 = 93
            98 - 5 = 93    
so answer of 95 x 98 = 9310

Squaring Numbers ending in 9

Squaring Numbers ending in 9
To square numbers ending in 9 like 19, 29, 39, 49....you know square of 9 is 9 x 9= 81, you can use this for speedy calculation. Now to the technique let me explain with example

1^st example 19²

step 1 : Add 1 to the number so that the number will be ending in 0
             19+1 =20
step 2 : find square of it as it ends in zero finding its square is easy.
              20²  = 400
step 3 : Add the 19 to 20
              19 + 20 = 39
step 4 : subtract the result of step 3 from resutl of step 2 and that will be your answer
              400 - 39= 361
              thus 19²  = 361

2^nd example 79²

step1 : 79+1 =80

step2 : 80²  = 6400

step3 : 79+80 =159

step4 : 6400-159=6241

thus 79²  = 6241

Squaring Numbers ending in 5

Squaring Numbers ending in 5
To square numbers ending in 5 like 15, 25, 35, 45....you know square of 5 is 5 x 5 = 25, you can use this for speedy calculation. Now to the technique let me explain with example

1^st example 15²

step 1 : Separate digit 5 from the number 15 then the remaining digit is 1
step 2 : add 1 to the remaining digit(s) here
              1 +1 = 2
step 3 : Multiply the number from step 1 and step 2
              1 x 2 = 2
step 4 : write 5² ie 25 after the result of step 3 ie 225
              thus 15²  = 225

2^nd example 95²

step1 : seperating 5 the remainng digit is 9

step2 : 9 +1 =10

step3 : 9 x 10 = 90

step4 : 95²=9025

Squaring Numbers ending in 3

Squaring Numbers ending in 3
To square the numbers ending in 3like 13, 23,33, 43..upto 93. there is an easy method let me explain with an example.

1^st example 13²

step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
1²=1
3²=9
step 2 : multiply the tens digit of the number to be squared to 6 and it will be the tens digit of the square
here 1x4 =4
1 9
 6
---------
169
---------
so the square of 13 is 169.

2^nd example 43²
step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
4²=16
3²=9
step 2 : multiply the tens digit of the number to be squared to 6 and it will be the tens digit of the square
here 4x6 =24
16  9
  24
-------------
1849
-------------
so 43²=1849

Squaring Numbers ending in 2

Squaring Numbers ending in 2
To square the numbers ending in 2 like 12, 22,32, 42 .upto 92. there is an easy method let me explain with an example.

1^st example 12²

step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
1²=1
2²=4
step 2 : multiply the tens digit of the number to be squared to 4 and it will be the tens digit of the square
here 1x4 =4
1 4 +
  4
---------
144
---------
so the square of 12 is 144.

2^nd example 42²
step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
4²=16
2²=4
step 2 : multiply the tens digit of the number to be squared to 4 and it will be the tens digit of the square
here 4x4 =16
16  4+
  16
-------------
1764
-------------
so 42²=1764

SQUARING numbers ending in 4

Squaring Numbers ending in 4
To square the numbers ending in 4 like 14, 24,34, 44..upto 94. there is an easy method let me explain with an example.


1^st example 14²


step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
1²=1
4²=16
step 2 : multiply the tens digit of the number to be squared to 8 and it will be the tens digit of the square
here 1x8 =8
1 16
   8
---------
196
---------
so the square of 14 is 196.

2^nd example 44²

step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
4²=16
4²=16

step 2 : multiply the tens digit of the number to be squared to 8 and it will be the tens digit of the square
here 4x8 =32
1616
  32
-------------
1936
-------------
so 44²=1936

SQUARES of numbers ending in 1

What do you mean by squaring a number?
Squaring means multiplying a number by itself.
example: squaring 3 means 3 multiplied by 3 (3x3) it will be written as 3² =9
Now lets move on to the funda..
Quick mental calculations can help in solving problems faster and practice of this can become a gift
We can find the squares using some technique this will help find the squares faster.

Squaring Numbers ending in 1

This is the short cut method to find out squares of numbers ending in 1 like 11,21,31,41,121,131 etc if we go for multiplying the numbers it will take longer time

1^st example 21²

step 1 :  subtact 1 from the number, so that the number ends in zero.
                       21-1=20
step 2 : find the square of the difference, its easy to square numbers ending with 0.
                       20² = 20x20 = 400
step 3 : add the number we now squared ie 20 and to the number to be squared ie 21
                       20+21=41
step 4 :add the result of step 2 to step 3 this will give you the answer of 21²
                       400 + 41 =441.
so 21² =441.

2^nd example 41²

step 1 : 41 - 1= 40

step 2 : 40² =40 x 40 = 1600

step 3 :40 + 41 = 81

step 4 : 1600 + 81 = 1681

so 41² =1681