脱式计算(能用简便算法的,要写出简便过程)24×10.5-3549÷39 7 10 ÷[( 3 5 -

2025-04-25 09:56:41
推荐回答(1个)
回答1:

(1)24×10.5-3549÷39,
=24×(10+0.5)-91,
=240+12-91,,
=252-91,
=161;

(2)
7
10
÷
[(
3
5
-
1
4
)×12],
=
7
10
÷[(
12
20
-
5
20
)×12],
=
7
10
÷[
7
20
×12],
=
7
10
÷
21
5

=
7
10
×
5
21

=
1
6


(3)2-
5
8
÷
25
28
-
3
10

=2-
5
8
×
28
25
-
3
10

=2-
7
10
-
3
10

=2-(
7
10
+
3
10
),
=2-1,
=1;

(4)
8
15
÷
1
6
-
7
15
×
6,
=
8
15
×
6-
7
15
×
6,
=(
8
15
-
7
15
)×6,
=
1
15
×
6,
=
2
5