早教吧 育儿知识 作业答案 考试题库 百科 知识分享

计算下面各题(能简算的要简算):(1)2.6×3.5+2.6×5.5+2.6(2)(25+14)÷23(3)113÷839+911×1112(4)78×10.1.

题目详情
计算下面各题(能简算的要简算):
(1)2.6×3.5+2.6×5.5+2.6          
(2)(
2
5
+
1
4
)÷
2
3

(3)
1
13
÷
8
39
+
9
11
×
11
12
                   
(4)78×10.1.
▼优质解答
答案和解析
(1)2.6×3.5+2.6×5.5+2.6     
=2.6×(3.5+5.5+1)
=2.6×10
=26;
     
(2)(
2
5
+
1
4
)÷
2
3

=
13
20
×
3
2

=
39
40


(3)
1
13
÷
8
39
+
9
11
×
11
12
         
=
3
8
+
3
4

=
9
8


(4)78×10.1.
=78×(10+0.1)
=78×10+78×0.1
=780+7.8
=787.8.