Simple calculation of 9.9 * 9.9 + 0.9

Simple calculation of 9.9 * 9.9 + 0.9

9.9*9.9+0.9
=9.9x(10-0.1)+0.9
=9.9x10-9.9x0.1+0.9
=99-0.99+0.9
=99-0.09
=98.91
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