Shortcut to Find Square of A Number: Final Lesson

January 06, 2016
Dear Readers,
Yesterday I have shared you how to find Square of a number in Lesson One. Today I am sharing you the last rule and this is very important. By this rule you can fine square of any number. Let’s start.

Shortcut to Find Square of A Number: Final Lesson

At first, separate the numbers like “Numbers Close to 50”, “Numbers Close to 1000”, “Numbers Close to 150”, “Numbers Close to 200”, “Numbers Close to 250”, “Numbers Close to 300”, and so on.

In previous lesson, you found the square of 10, 11 &15, 20, 21 & 25, 30, 31 & 35 so on. Now we find the square of the rest numbers. You may use today’s rule for all numbers. But, I prefer Rules of Lesson One for these numbers.


Rule: 1 Number Closes to 50

25 + X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )

If we find the square of 53 (close to 50), then
532 = 25 + X | X2       
532 = 25 + 3 | 32
532 = 28 | 09
532 = 2809

If we find the square of 53 (close to 50), then
462 = 25 + X | X2       
462 = 25 - 4 | 42
462 = 21 | 16
462 = 2116

Rule: 2 Number Closes to 100

100 + 2X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )

If we find the square of 104 (close to 100), then
1042 = 100 + 2X | X2 
1042 = 100 + 2.4 | 42
1042 = 100 + 8 | 16
1042 = 10816

If we find the square of 92 (close to 100), then
922 = 100 + 2X | X2   
922 = 100 – 2.8 | 82
922 = 100 -16 | 64
922 = 84 | 64
922 = 8464

Rule: 3 Number Closes to 150

225 + 3X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )

If we find the square of 167 (close to 150), then
1672 = 225 + 3X | X2 
1672= 225 + 3.17 | 172
1672 = 225 + 51 | 289
1672= 276 | 289 (add 2 with 6, makes 8)
1672= 27889

If we find the square of 134 (close to 150), then
1342 = 225 + 3X | X2 
1342 = 225 – 3.16 | 162
1342 = 225 - 48 | 256
1342 = 177 | 256 (add 2 with 7, makes 9)
1342 = 17956

You can try it for other numbers. Rules are given below:


Rule: 4 Number Closes to 200

400 + 4X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )


Rule: 5 Number Closes to 250

625 + 5X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )


Rule: 6 Number Closes to 300

900 + 6X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )


Rule: 7 Number Closes to 350

1225 + 7X | X2

(X takes -Value when the number is below 50 or vice versa & the digit will be two after | )


Try it for numbers close to 400, 450, 500, 550 so on.

For Any Query Kindly Comment.

Thanks!!

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