(2890+5/6+7/8+7/10)÷(5/6+7/8+7/10)

问题描述:

(2890+

5
6
+
7
8
+
7
10
)÷(
5
6
+
7
8
+
7
10

5
6
+
7
8
+
7
10
为a,
(2890+
5
6
+
7
8
+
7
10
)÷(
5
6
+
7
8
+
7
10

=(2890+a)÷a,
=2890÷a+a÷a,
=2890÷a+1,
=2890÷(
5
6
+
7
8
+
7
10
)+1,
=2890÷
289
120
+1,
=1200+1,
=1201.