7/3 - 2/4 = 28/12 - 6/12= 22/12 = 1 целая 10/12 = 1 целая 5/6
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1 1/2 - 2 3/4 = 3/2 - 11/4 = 6/4 - 11/4 = - 5/4 = - 1 целая 1/4
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2/8 - 1 3/5=2/8 - 8/5 =10/40-64/40= - 54/40= - 1целая 14/40 = -1целая 7/20