1) (-1 2/5 + (- 3,6)) + (-2 5/6 + (- 2/3))
1. -1 2/5 + (- 3,6) = - 7/5 + (- 3 6/10) = - 7/5 + (- 3 3/5) = - 7/5 + (- 18/5) = - 25/5 = -5
2. -2 5/6 + (- 2/3) = - 17/6 + (-2/3) = - 17/6 + (- 4/6) = - 21/6 = - 3 3/6 = -3 1/3
3. -5 + (- 3 1/3) = - 8 1/3
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2) (- 5/8 + (- 3/4)) + (-7,6 + (-2 2/5))
1. - 5/8 + (- 3/4) = - 5/8 + (- 6/8) = - 11/8 = - 1 3/8
2. -7,6 + (-2 2/5) = - 7 6/10 + (- 12/5) = -7 3/5 + (- 12/5) = - 38/5 + (- 12/5) = - 50/5 = -10
3. -1 3/8 + (-10) = - 11 3/8