5/8 + 5/6 + 7/12 = 30/48 + 40/48 + 28/48 = 98/48 =2 2/48 = 2 1/24
1/5 + 3/8 - 2/9 = 72/360 + 135/360 - 80/360 = 127/360
1/4 + 2/9 -5/36 = 9/36 + 8/36 - 5/36 = 12/36 = 1/3
X÷12=211-109
x÷12=102
x=102×12
x=1224
Проверка:
1224÷12+109=211
Криво-косо, но хоть как-то)
1)(8+5)*2-67*20=8+5=13*2=26 67*20=1340 1340-26=1314