计算下面各题,能用简便方法的要用简便计算.2.5×(2.9+2.9+2.9+2.9)(23?59×38)÷716(16+19?

2025-05-09 16:15:18
推荐回答(1个)
回答1:

(1)2.5×(2.9+2.9+2.9+2.9),
=2.5×4×2.9,
=10×2.9,
=29;

(2)(

2
3
-
5
9
×
3
8
÷
7
16

=(
2
3
-
5
24
÷
7
16

=
11
24
÷
7
16

=1
1
21


(3)(
1
6
+
1
9
-
1
12
)×36,
=
1
6
×36+
1
9
×36-
1
12
×36,
=6+4-3,
=10-3,
=7;

(4)4÷
4
9
-
4
9
÷16,
=9-
1
36

=8
35
36