1 11/15 + 3 4/15 : (14,6 - 12,8 * 1,25) = - 11/15
1) 12,8 * 1,25 = 16
2) 14,6 - 16 = - 1,4
3) 3 4/15 : (- 1,4)= 49/15 : ( - 14/10) = 49/15 * (-10/14) = 49/3 * (- 2/14) = - 98/42 = - 2 14/42 = - 2 1/3
4) 1 11/15 + (- 2 1/3) = 26/15 - 7/3 = 26/15 - 35/15 = - 11/15