计算:(1)(?48)÷74÷(?12)×74;         (2)16+(?27)+(?56)+57;(3)1.25×(?2)3?[(?4)

2024-12-30 04:35:39
推荐回答(1个)
回答1:

(1)原式=(-48)×

4
7
×(-
1
12
)×
7
4

=(-48)×(-
1
12

=4;

(2)原式=
1
6
-
2
7
-
5
6
+
5
7

=(
1
6
-
5
6
)-(
2
7
-
5
7

=(-
4
6
)-(-
3
7

=-
5
21


(3)原式=1.25×(-8)-[(-4)÷
4
9
+1]+(-1)
=-10-[-9+1]+(-1)
=-10+8-1
=-3.