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计算下面各题,能用简便方法的要用简便方法.

来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/11/10 22:10:36
计算下面各题,能用简便方法的要用简便方法.
(1)
4
11 ×
1
7 ÷
4
7 ,
=
4
11 ×
1
7 ×
7
4 ,
=
4
11 ×(
1
7 ×
7
4 ),
=
4
11 ×
1
4 ,
=
1
11 ;

(2)
11
21 ×
1
8 +
10
21 ÷8,
=
11
21 ×
1
8 +
10
21 ×
1
8 ,
=(
11
21 +
10
21 )×
1
8 ,
=1×
1
8 ,
=
1
8 ;

(3)(15-15×
4
5 )×
7
24 ,
=(15-12)×
7
24 ,
=3×
7
24 ,
=
7
8 ;

(4)[
4
5 -0÷(
1
3 +
2
5 )]×
5
8 ,
=[
4
5 -0]×
5
8 ,
=
4
5 ×
5
8 ,
=
1
2 ;

(5)(34+
34
47 )÷17,
=(34+
34
47 )×
1
17 ,
=34×
1
17 +
34
47 ×
1
17 ,
=2+
2
47 ,
=2
2
47 ;

(6)(
5
6 +
2
9 )×
4
5 ÷
19
20 ,
=
19
18 ×
4
5 ×
20
19 ,
=
19
18 ×
20
19 ×
4
5 ,
=
10
9 ×
4
5 ,
=
8
9 .