1/5x-4/3+7/2
-4/15+7/2
-8/30+105/30
97/30
4/5 : (-3/7)-7/10
4/5x-7/3-7/10
-28/15-7/10
-56/30-21/30
-77/30
13/7+(-8/7):(-4/5)
13/7+(-8/7)x-5/4
13/7+40/28
52/28+40/28=92/28=23/7
7/3+3/2x-10/21
7/3+(-30/42)
108/42-30/42=78/42=13/7
5/8+(-3/4) : (-9/16)
5/8+(-3/4)x(-16/9)
5/8+48/36
45/72+96/72=141/72ou47/24
6/5-(-1/9)x(-3/4)
6/5-3/36
436/360-30/360
406/360