\(\frac35-(\frac12)2+\frac9{10} \\~\\ =\,\frac35-\frac22+\frac9{10} \\~\\ =\,\frac{3\cdot2}{5\cdot2}-\frac{2\cdot5}{2\cdot5}+\frac9{10} \\~\\ =\,\frac{6}{10}-\frac{10}{10}+\frac9{10} \\~\\ =\,\frac{6-10+9}{10} \\~\\ =\,\frac{5}{10} \\~\\ =\,\frac12\)
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