问题 解答题
用递等式计算.
(1)2180+540÷18×24
(2)1
5
7
×(5÷
5
6
-
5
6
÷5)
(3)4
1
5
÷[2.5-0.4×(2
4
5
-1.05)]
(4)[1-(4
1
3
-1.75×2)]÷2
1
2
答案

(1)2180+540÷18×24,

=2180+30×24,

=2180-720,

=1460;

(2)1

5
7
×( 5÷
5
6
-
5
6
÷5 ),

=1

5
7
×( 6-
5
6
÷5 ),

=1

5
7
×( 6-
1
6
),

=

12
7
×
35
6

=10;

(3)4

1
5
÷[2.5-0.4×(2
4
5
-1.05)],

=4

1
5
÷[2.5-0.4×1.75],

=4

1
5
÷[2.5-0.7],

=4

1
5
÷1.8,

=

21
5
×
5
9

=

7
3

(4)[1-(4

1
3
-1.75×2)]÷2
1
2

=[1-(4

1
3
-3.5)]÷2
1
2

=[1-

5
6
2
1
2

=

1
6
×
2
5

=

1
15

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