能简便的要简便.①(78-516)×(59+23)②813÷7+17×613③234×25+14÷52④16÷[917×(34+23)]⑤1213×37+47×1213+1213⑥99×99100⑦100×9899.-数学

23)],
=
1
6
÷[
9
17
×
17
12
],
=
1
6
÷
3
4

=
2
9


12
13
×
3
7
+
4
7
×
12
13
+
12
13

=
12
13
×(
3
7
+
4
7
+1),
=
12
13
×2,
=
24
13


⑥99×
99
100

=(100-1)×
99
100

=100×
99
100
-1×
99
100

=99-
99
100

=98
1
100


⑦100×
98
99

=(99+1)×
98
99

=99×
98
99
+1×
98
99

=98+
98
99

=98
98
99

据专家权威分析,试题“能简便的要简便.①(78-516)×(59+23)②813÷7+17×613③234×25+14÷52④1..”主要考查你对  运算定律和简便算法,分数的简便算法  等考点的理解。关于这些考点的“档案”如下:

运算定律和简便算法分数的简便算法