175.
1) -6,47+8,32+6,47+(-7,32)=6,47-6,47+8,32-7,32=0+1=1
2) 4,46+(-12,11)+7,11+(-8,46)= 4,46-8,46+7,11-12,11= -4-5=-9
176.
1) -43+(-60)+18+36+(-19)= 18-19-43-60+36= -44-24=-68
2) -2,43+6,31+(-3,21)+0,49+4,87 = 4,87-2,43+6,31+0,49 -3,21= 2,44-3,21+6,8= 2,44+3,59 = 6,03
3) -19/42 +(-9/16)+(-11/42)+5/16= -11/42 - 19/42 +5/16 - 9/16 = -30/42 -4/16 = -5/7 - 2/4 = (-20-14)/28 = -34/28 = -17/14 = -1 целая 3/14
177.
5,43+х+(-2,6)+(-7,8)+у+(-6,43) = х+у+ 5,43-6,43-10,4 = х+у-11,4
При х=-12,6, у= -3,4
-12,6-3,4-11,4 = -16-11,4= -27,4