b) 2 x 2 x 2:4 =
=4×2:4
=8:4
=2
a)7+7+3-6+2=
=14+3-6+2
=17-6+2
=11+2
=13
3-2 +2 -1 + 2 =
=1+2-1+2
=3-1+2
=2+2
=4
5x6: 10x0x9 =0
2-2 +2 - 2 + 2 =
=0+2-2+2
=2-2+2
=0+2
=2
8:4 x 9:6 X 1 =
=2×9:6×1
=18:6×1
=3×1
=3
5 + 5 + 5 - 10 + 2 =
=10+5-10+2
=15-10+2
=5+2
=7
3x3x3:9 x6:2=
=9×3:9×6:2
=27:9×6:2
=3×6:2
=18:2
=9
20 - 13 +28+2=
=7+28+2
=35+2
=37
81:9 X1:3:3=
=9×1:3:3
=9:3:3
=3:3
=1