问题 解答题
脱式计算.
4+
7
10
x=102
x-
1
4
x=
3
8
50%x-33%x=510
4
5
×
2
3
+
1
5
÷
3
4
5
6
×5÷
5
6
÷5
2
9
÷5+
1
5
×
7
9
答案

(1)4+

7
10
x=102,

4+

7
10
x-4=102-4,

7
10
10
7
=98×
10
7

x=140;

(2)x-

1
4
x=
3
8

3
4
x=
3
8

3
4
4
3
=
3
8
×
4
3

x=

1
2

(3)50%x-33%x=510,

0.17x=510,

0.17x÷0.17=510÷0.17,

x=3000;

(4)

4
5
×
2
3
+
1
5
÷
3
4

=

2
5
×
4
3
+
1
5
×
4
3

=(

2
5
+
1
5
)×
4
3

=

3
5
×
4
3

=

4
5

(5)

5
6
×5÷
5
6
÷5,

=

5
6
×5×
6
5
×
1
5

=1;

(6)

2
9
÷5+
1
5
×
7
9

=

2
9
×
1
5
+
1
5
×
7
9

=

1
5
×(
2
9
+
7
9
),

=

1
5
×1,

=

1
5

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