become expert | help | login
refer a friend - earn nickels!!
 advanced
originally posted here on IIT-JEE / AIEEE community   
like the article? email it to a friend.  email this article!  
   Trick to find squares of numbers which have 5 as their last digit
posted on 12 Nov 2011 13:26:15 IST    1375 views    19 comments
« Back to Articles
Tagged with:   Awaiting Review for Nickels

Here is an Easy way to find Squares of numbers which contain 5 as their last digit..

Consider the digits written before 5 as a single number and multiply it be its succcessor and then write it and put 25 as the last two digits of it...

For example:

to find square of 15::  (1*2)=2 and then write 25 at the end ,ie. 225

similarly to find square of 25:: (2*3)=6 and then write 25 at the end i.e, 625

for finding square of 105:: (10*11)=110 and then write 25 at the end ,i.e, 11025

PLS RATE IT IF YOU LIKE IT !!

Some of The Related Articles:

What is PSEUDO FORCE ?

Image formation in Plane Mirror @ Infinity Distance

Kaprekar Transformation for 3-Digit Numbers

About the Author:
RISHABH BAJPAI (240)

Olaaa!! Perrrfect answer.  48  [48 rates]

RISHABH BAJPAI's Avatar

total posts: 233    
online Offline
  this article:   60 points  (with 12  Olaaa!! Perrrfect answer.   in 12   votes   )     [?]
 
You have to be logged on to rate
  
Pritha is offline comment by Pritha      (posted on 13 Nov 2011 11:57:53 IST)
    niceeeeee...!!
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 13 Nov 2011 13:45:51 IST)
    thnks!!!
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 14 Nov 2011 10:45:21 IST)
    isnt it gud guys???
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 22 Feb 2012 18:11:41 IST)
    ???
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 16 Mar 2012 12:31:43 IST)
    ????
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 19 Mar 2012 11:39:03 IST)
    thnks 4 d lyks...
Anjali Goyal is offline comment by Anjali Goyal      (posted on 19 Mar 2012 14:34:47 IST)
    ya...its nicee....
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 19 Mar 2012 19:18:58 IST)
    thnks
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 19 Mar 2012 19:25:01 IST)
    n do rate it..
hemang is offline comment by hemang      (posted on 20 Mar 2012 12:41:17 IST)
    

i will show how it works.

the numbers are of the form 10n + 5.

(10n+5)^2 = 100n^2 + 100n + 25.

or, 100n(n+1) + 25.

since we are multiplying by 100, at least 2 zeroes must be at the end , so adding 25 will result in the last two digits be 25.

n(n+1) is also justified.

 

 

RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 1 May 2012 21:08:27 IST)
    rite....
PO The Legend Of Awsomeness is offline comment by PO The Legend Of Awsomeness      (posted on 1 May 2012 21:46:35 IST)
    good work rishabh
PO The Legend Of Awsomeness is offline comment by PO The Legend Of Awsomeness      (posted on 1 May 2012 21:46:59 IST)
    it's awesome
sushma is offline comment by sushma      (posted on 2 May 2012 09:05:54 IST)
    

 its very nice

RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 2 May 2012 10:01:45 IST)
    thnks guys....
deepa is offline comment by deepa      (posted on 5 May 2012 18:35:55 IST)
    very nice
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 6 May 2012 12:30:17 IST)
    hit like then....
Ujjaval Sinha is offline comment by Ujjaval Sinha      (posted on 10 May 2012 09:18:53 IST)
    gr8 man. please post some more of these kinda shortcuts. plz...
RISHABH BAJPAI is offline comment by RISHABH BAJPAI      (posted on 10 May 2012 10:35:55 IST)
    hit like buddy....
Sponsored Links
Free Exam Papers ?
unit, model, solved papers
IIT, Medical, CBSE. Get Free Now!

vriti.com/Scholarship