how to find the square of a number from 30-70 easily

hi ,
I am prakash back gaon with my second tutorial.
here I am going to make you learn how to find the the square of a number between 30 and 70 easily.
whats in between 30  and 70 ?
its 50 and we are going to take this number as our most important value.
lets see how .
firstly we find the square of 54
guys bring out your calculators and simply do ity using your calculator
you get 2916.
now we use our rule .
how much more is 54 from 50 ---- its 4
so take 25 add four to it for the first two digit
 for the send two digits sqaure 4 and place it there
let me show you
                      (25+4)(4square)=2916
let me take one more example
lets us take  59 square
how much more from 50? ans---- 9
so take 25 add 9
then for next two digits square the difference
that's 81
                                                    (25+9)(9square)=3481
thats it.
now for a number lower that 50
take 47 . how much less than 50? thats 3
do just the opposite for 1st two digit means subract from 25
we get 22
the process for next two digits remain same thats square the number .
                                                    (25-3)(3 square)=2209
if you take 61 you will get  121 as the last two values and 36 as first two. but we can only have 4 digits so add one to 36 and make 37
 that means you get 3721
any questions? use comments box

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