4целых4/9-3 целых 7/9

4целых -3 целых = -1  7/9-4/9=3/9 равно -1 целая 3/9

4 [latex] \frac{4}{9} [/latex] - 3 [latex] \frac{7}{9} [/latex] = 3 [latex] \frac{13}{9} [/latex] - 3 [latex] \frac{7}{9} [/latex] = [latex] \frac{6}{9} [/latex] = [latex] \frac{2}{3} [/latex]