Squaring numbers near 100

Use this process to conveniently square numbers near and below 100, and near and above 100:

*To square numbers near and below 100:     ex. 94×94=8836

-From 100 subtract the number being squared.   100-94=6

-Square this difference. This yields the last two digits of the answer.   6×6=_ _36

-Subtract the difference above from the number being squared. This yields the first digits of the answer.   94-6=88_ _

*To square numbers near and above 100:      ex. 107×107=11449

-From the number being squared subtract 100.   107-100=7

-Square this difference. This yields the last two digits of the answer.   ex. 7×7=_ _49

-Add the difference above to the number being squared. This yields the first digits of the        answer.   ex. 7+107=114_ _

Try these:  92×92=8464      98×98=9604      103×103=10609      111×111=12321

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