(1)108÷18×75+25×6
=6×75+25×6
=450+150
=600;
(2)9.6÷3.2+5.1×4
=3+20.4
=23.4;
(3)(
+4 5
)÷1 4
+7 3
7 10
=
÷21 20
+7 3
7 10
=
+9 20
7 10
=
;23 20
(4)[
-〔1 2
-3 4
〕]÷3 5
7 10
=[
-1 2
]÷3 20
7 10
=
÷7 20
7 10
=
.1 2