=4 14/21:(-8/21)+(8 25/30 -4 24/30) : 3 3/10= -12+4 1/30 : 3 3/10= -12 - 1 2/9 = -13 2/9
4 2/3:(-8/21)+(8 5/6-4 4/5) : 3 3/10=1. 4 2/3:(-8/21)=14/3*-8/21=-112/632. (8 5/6-4 4/5)=53/6*5-24/5*6=265/30-144/30=121/303. 121/30 : 3 3/10=121/30*10/33=1210/990=121/994.-112/63+121/99=-112/63*99+121/99*63=-11088/6237+11979/6237=891/6237=1/7
=4 14/21:(-8/21)+(8 25/30 -4 24/30) : 3 3/10= -12+4 1/30 : 3 3/10= -12 - 1 2/9 = -13 2/9
4 2/3:(-8/21)+(8 5/6-4 4/5) : 3 3/10=
1. 4 2/3:(-8/21)=14/3*-8/21=-112/63
2. (8 5/6-4 4/5)=53/6*5-24/5*6=265/30-144/30=121/30
3. 121/30 : 3 3/10=121/30*10/33=1210/990=121/99
4.-112/63+121/99=-112/63*99+121/99*63=-11088/6237+11979/6237=891/6237=1/7