3) - 1,5 - 3 4/5 - 8 3/20 = - 1 5/10 - 3 4/5 - 8 3/20 = - 1 10/20 - 3 16/20 - 8 3/20 =
= - (1 10/20 + 3 16/20 + 8 3/20) = - 12 29/20 = - 13 9/20
4) - 2 5/8 - 9,25 - 3/4 = - 2 5/8 - 9 25/100 - 3/4 = - 2 5/8 - 9 1/4 - 3/4 = - 2 5/8 -
- 9 2/8 - 6/8 = - (2 5/8 + 9 2/8 + 6/8) = - 11 13/8 = - 12 5/8