问题 解答题
用简便方法计算.
4
5
×
1
3
+
1
5
×
1
3

4
7
×(
3
4
÷
2
3
-
3
2
×
1
4
)

(
2
9
×
3
4
+
1
4
÷
9
2
2
9
答案

(1)

4
5
×
1
3
+
1
5
×
1
3

=(

4
5
+
1
5
)×
1
3

=1×

1
3

=

1
3

(2)

4
7
×(
3
4
÷
2
3
-
3
2
×
1
4

=

4
7
×(
3
4
×
3
2
-
3
2
×
1
4

=(

3
4
-
1
4
)×
3
2
×
4
7

=

1
2
×
3
2
×
4
7

=

3
7

(4)(

2
9
×
3
4
+
1
4
÷
9
2
÷
2
9

=(

2
9
×
3
4
+
1
4
×
2
9
÷
2
9

=(

3
4
+
1
4
)×
2
9
÷
2
9

=1×1,

=1.

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