作业帮 > 数学 > 作业

脱式计算,能用简便算法的要用简便算法.

来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/04/30 01:20:57
脱式计算,能用简便算法的要用简便算法.
5.4×
9
10
+3.6÷
10
9
+0.9
脱式计算,能用简便算法的要用简便算法.
①5.4×
9
10+3.6÷
10
9+0.9
=5.4×0.9+3.6×0.9+0.9×1
=0.9×(5.4+3.6+1)
=0.9×10
=9;
②78×
3
79
=(79-1)×
3
79
=79×
3
79−
3
79×1
=3-
3
79
=2
76
79;
③6-3
1
4+
3
4
=3+3+
3
4-3
3
4
=3+[(3+
3
4)-3
3
4]
=3;

5
9×[
3
4-(
7
16-
1
4)]
=
5
9×[(
3
4+
1
4)-
7
16]
=
5

9
16
=
5
16;
⑤[47-(18.875-1÷
8
15)]÷0.46×
46
25
=[47-(18.875-1.875)]×
100
46×
46
25
=[47-(18.875-1.875)]×4
=[47-17]×4
=30×4
=120.