### Squaring of a number ending with 5

After you read this article , you would be able to find the answers to the square of numbers ending with 5, almost instantly and **mentally**.

For example , you squares of 35 , 75 , 95 , 105 etc.

__Here's how to do it__,

Imagine in mind the number, suppose 35 in your mind to be of two parts "3" and "5" ( If it is difficult for you to imagine , write it at a piece of paper )

Now, * multiply the first part of the number with a number that is one ( 1 ) greater than it* ( Here,

*"*as

**3**" is to be multiplied with "**4**"**3 + 1 = 4**) , this will be the first part of your final answer.

Here,

**3 x 4 = 12**, so ,

__12 will be the first part of your final answer__.

Next we know

**5**, so

^{2}=25**25**will be the next part of your final answer.

SO, your final answer becomes 1225 .

Likewise,

**95**(

^{2}=**9 x 10**becomes the first part, and

**25**becomes the next part )

**=**

**( 90 , 25 )**[In the above step "9" is multiplied with "10" since 9 + 1 = 10 ]

**= 9025**[

__Final answer__]

Taking another example,

**105**( 10 x 11 becomes the first part, and 25 becomes the next part )

^{2}=[

**Note :**

__]__

*The first part will always be the number(s) except 5*So,

105

^{2}=( 110 becomes the first part, and 25 becomes the next part )

=

**11025**[

__Final answer__]

**Self-Exercies:-**a)

__55__= ??

^{2}b)

__65__= ??

^{2}c)

__125__= ??

^{2}d)

__205__

^{2}= ??

## 3 comments:

Cool.I never knew this.Thanks.

PLEASE ADD SOME MORE EXAMPLES

thanks for explanation its so easy to understand

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