1) 3/8 : (-9/16) = 3/8 * (-16/9) = - (1*2)/(1*3) = - 2/3
2) 5/12 * (-6) = - 5/2 = - 2 целых 1/2
3) 5 1/3 - 6 1/4 = 5 4/12 - 6 3/12 = - (6 3/12 - 5 4/12) = - (5 15/12 - 5 4/12) = - 11/12
4) 1/2 + 3/5 = 5/10 + 6/10 = 11/10 = 1 целая 1/10
5) 4 - 1 3/5 = 3 5/5 - 1 3/5 = 2 целых 2/5