1/2 + 5/6 разделить ( 1 целая 1/2 - 3/4)*1целая 4/5

= 1/2 + 5/6 : (3/2 - 3/4) * 9/5 = 1/2 + 1/6 : 3/4 * 9 = 1/2 + 1/6 * 4/3 * 9 = 1/2 + 1/3 × 2 × 3 = 1/2 + 2 = 5/2 = 2 1/2

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