问题 解答题
计算下面各题,能用简便方法算的要用简便方法算
7
13
×
5
6
+
5
6
÷
13
6

4
15
×[(
3
4
-
2
5
)÷
15
4
]
7
8
-
4
5
+
3
8
×
1
3

25×1.25×4×8.
答案

(1)

7
13
×
5
6
+
5
6
÷
13
6

=

7
13
×
5
6
+
5
6
×
6
13

=(

7
13
+
6
13
)×
5
6

=1×

5
6

=

5
6

(2)

4
15
×[(
3
4
-
2
5
)÷
15
4
],

=

4
15
×[(
15
20
-
8
20
)×
4
15
],

=

4
15
×[
7
20
×
4
15
],

=

4
15
×
7
75

=

28
1125

(3)

7
8
-
4
5
+
3
8
×
1
3

=

7
8
-
4
5
+
1
8

=

7
8
+
1
8
-
4
5

=1-

4
5

=

1
5

(4)25×1.25×4×8,

=(25×4)×(1.25×8),

=100×10,

=1000.

单项选择题
单项选择题