(8 7/12 -2 17/36)*2 7/10-4 1/3 как это решить????

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$(8 \frac{7}{12} - 2 \frac{17}{36} ) \times 2 \frac{7}{10} - 4 \frac{1}{3} = (8 \frac{21}{36} - 2 \frac{17}{36} ) \times 2 \frac{7}{10} - 4 \frac{1}{3} = 6 \frac{4}{36} \times \frac{27}{10} - 4 \frac{1}{3}= 6 \frac{1}{9} \times \frac{27}{10} - 4 \frac{1}{3} = \frac{55 \times 27}{9 \times 10} - 4 \frac{1}{3} = \frac{11 \times 3}{2} - 4 \frac{1}{3} = \frac{33}{2} - \frac{13}{3} = \frac{99}{6} - \frac{26}{6} = \frac{73}{6} = 12 \frac{1}{6}$
ОТВЕТ: 12 1/6