Square 2 Digit Number:WITH UP-DOWN Method
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Square a 2 Digit Number, for this example 37:
> Look for the nearest 10 boundary
> In this case up 3 from 37 to 40.
> Since you went UP 3 to 40 go DOWN 3 from 37 to 34.
> Now mentally multiply 34x40
> The way I do it is 34x10=340;
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> Double it mentally to 680
> Double it again mentally to 1360
> This 1360 is the FIRST interim answer.
> 37 is "3" away from the 10 boundary 40.
> Square this "3" distance from 10 boundary.
> 3x3=9 which is the SECOND interim answer.
> Add the two interim answers to get the final answer.
> Answer: 1360 + 9 = 1369
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