Вычислети: 1) 2/3 + ( - 10 1/3 ); 2) - 3/8 + 4/7; 3) 3/5 + (- 1 5/6 ); 4) 2/9 + ( - 1 5/6); 5) 4/5 + ( - 2/7 ); 6) - 9 + 2/9.

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1) 2/3+(-10 1/3) = 2/3-31/3 = -29/3 = -9 2/3

2) -3/8+4/7 = 4/7-3/8 = 11/56

3) 3/5+(-1 5/6) = 3/5-11/6 = - 37/30 = -1 7/30

4) 2/9+(-1 5/6) = 2/9-11/6 = -27/18 = -1 9/18

5) 4/5+(-2/7) = 4/5-2/7 = 18/35

6) -9+2/9 = 2/9-9 = -79/9