A) 162:9-7 __162:(9-7)=
18-7__ 162:2
11 <81
B) (40-30):10___ 40-(30:10
10:10___40-3
1 <37
C) 68-12×(4-6:2)___[68-(12×4-6)]:2
68-12×(4-3)__[68-(48-6)]:2
68-12×1___ (68-42):2
68-12___26:2
56>13
D) (100-10):10+90:3___[(100-10):10+90]:3
90:10+90:3___(90:10+90):3
9+30___(9+90):3
39___ 99:3
39>33