Mental Maths Shortcut 5 squared Genius
Written by Kevin on June 22, 2007 – 8:21 am -Here is a really quick way to square any number with a 5 on the end.
Lets take
Ok, so what you have to do is split up the numbers, giving you
and 
Forget about the for the moment and do this:
Always add 1, adding 1 to the 4, so we get 4 + 1 = 5
Then multiply this answer, 5, by the original first number, 4
5 X 4 = 20
So what you have is 20 and
Everyone knows = 25 right? Well it does. This is what makes it easy.
Put the two answers together and that’s the answer!
2025
This works for any number ending in but when the numbers get over 100 it tends to get a little trickier with the multiplication.
Give it a try with another number.
Try 
, it isn’t difficult.
Split the numbers apart:
8 and
Again, forget about the
Add 1 to 8
8 + 1 = 9
Multiply 9 by the first number, which was 8
9 X 8 =72
Now, put all the numbers together, 72 and
= 25
So the answer is 7225
Try it out in a calculator once you have done it.
Posted in Mental Tips & Tricks, Vedic Maths |
21 Responses
to “Mental Maths Shortcut 5 squared Genius”
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- Jan 12, 2008: Ars Mathematica » Blog Archive » 24th Carnival of Mathematics
i read some of them
and i try to read rest of them later
tanx
it ’s so …
i dont find a word which cab be suitable for the blanck
but i think about it
goodluck
raha
I have gone through quick squaring of two/three digit numbers.It is very funny and interesting. What about squaring of more than 4,5…n digits? Can anyone teach me in such a very simple way as to be understood by a lame man?
Thanks
rs
Hey, I like the blog so far. I can’t seem to see the numbers. Somethine is missing?
Okay for some reason I can see them now. Good work! Keep it up!
it is a really useful technique. could it be used for 3 digit number as well square of 125
This is truly simple. I love it. I look forward to more.
Thanks Frankie, glad you like it.
Mental math is a useful type of math using many simple operations. Nothing difficult as its written form. The purpose is to be able to handle computation mentally. The information in this post is clearly explained. Well-done!
From: www.limeehai.com
Squaring of numbers ending at 5 is amazing. I have tried with 2 digit, 3 digit and 4 digits (though it took some time without a calculator).Actually this is a general technique to multiply numbers with beginning digits same and the sum of the ending digits equal to 10.
Take the numbers 24 and 26.
Both numbers have the first digit same (2) and the sum of the last digits (4 + 6) equal to 10. Now apply the following formula to multiply these numbers.
(2+1) * 2 | (4 * 6) => 6 | 24 = 624
Squaring of numbers ending at 5 is an extension of this general formula.
It is very simple and we don’t have to depend on calculator for squaring of numbers ending at 5. I expect more to see in future
Well done. All Goodluck to you
Sivakumar
please tell me how to do squares of 3 digits
Thanks
it is amazing
tell me how to do it for three digits squaring
Thanks
Yoganarayanan
thank u
for goving a wonderful collection in vadic maths
tell me how to memorize a multiplication table
amith
good tricks in mathematics which will be very useful to students in their competitive examinations
Squaring of numbers ending at 5 is amazing. Thanks for this . I am expecting more from you like this. Thanks a lot..
its amazing sir,expecting more from u like this.thanks a lot
thank u
for goving a wonderful collection in vadic maths
its amazing sir,expecting more from u like this.thanks a lot
That’s why Mathematics is so interesting.
Hopes getting bigger.
thanks for the shortcut method!
Excellent way of calculating things at lightening speed. MOre such techniques will b appreciated