2) не знаю
3) = -2,4+3,9=1,5
=-5,7-4,6=-10,3
=-7,1+13,79=6,69
=-6,2-21,48=-27,68
4) =-6/17-9/17=-15/17
=15/43-8/43=7/43
=-4/27-12/27=-16/27
=-47/61+32/61=-15/61
1) =-4,65-7,35+8=-12+8=-4
=21-16,8-13,2=21-30=-9
=-34,7+70-35,3=-70+70=0
=-18-5,44+2,56=18-8=10
2) =10/12+3/12=1 1/12
=-5/15-7/15=-12/15=-4/5
=10/36-27/36=-17/36
=-4/8+7/8=3/8