Ответ:
Пошаговое объяснение:
674.
(-3 1/4 +2 1/6)·(-2 2/11)-(-5/6+1 3/5)·(-4/5 -1,2)=(2 2/12 -3 3/12)·(-24/11)-(1 18/30 -25/30)·(-4/5 -6/5)=-1 1/12 ·(-24/11)-(48/30 -25/30)·(-2)=-13/12 ·(-24/11) -23/30·(-2)=(13·2)/11 +23/15=26/11 +1 8/15=2 60/165 +1 88/165=3 148/165
(-2 2/5 -1 1/3)·(-1 17/28)+(5 2/3 -8 3/4)·(-8 3/4 +5 2/3)=(-2 6/15 -1 5/15)·(-45/28)+(5 8/12 -8 9/12)²=-3 11/15 ·(-45/28)+(-3 1/12)²=-56/15 ·(-45/28)+(-37/12)²=2·3 +1369/144=6 1369/144=15 73/144
676.
(3/4 -4/5)·7,8-(2/3 +4/7)·(-7/13)=(15/20 -16/20)·39/5 -(14/21 +12/21)·(-7/13)=-1/20 ·39/5 -26/21 ·(-7/13)=-39/100 +2/3=200/300 -117/300=83/300
(3/7 -16/21)·(-2 2/7)+(11/15 +0,3)÷(-12 2/5)=(9/21 -16/21)·(-16/7)+(11/15 +3/10)·(-5/62)=-7/21 ·(-16/7)+(22/30+9/30)·(-5/62)=16/21 +31/30·(-5/62)=16/21 -1/(6·2)=16/21 -1/12=64/84 -7/84=57/84=19/28