问题
解答题
|
答案
(1)(
-4 5
)÷1 3 2 15
=
×7 15 15 2
=
;7 2
(2)
×(2 5
+5 6
)-3 4 1 5
=
×2 5
-19 12 1 5
=
-19 30 1 5
=
;13 30
(3)
÷1 3
+12 7
×2 3 7 12
=
×1 3
+7 12
×2 3 7 12
=(
+1 3
)×2 3 7 12
=1×7 12
=
;7 12
(4)[
+(1 6
-1 2
)]÷21 3
=[
+1 6
]÷21 6
=
×1 3 1 2
=
.1 6