1) 1 2/3 - 3,6 = 1 2/3 - 3 6/10 = 5/3 - 18/5 = 25/15 - 54/15 = - 29/15 = - 1 14/15
2) - 2 7/9 + 4 1/15 = - 25/9 + 61/15 = -125/45 + 183/45 = 58/45 = 1 13/45
3)- 1 14/15 : 1 13/45 = - 29/15 : 58/45 = - 29/15 * 45/58 = - 3/2 = - 1 1/2
4) - 1 1/2 * ( - 2,6) - 1 1/2 * (- 2 6/10) = - 3/2 * ( - 13/5) = 39/10 = 3 9/10