精英家教网 > 小学数学 > 题目详情
①(0.4×0.8)×(2.5×12.5)
②0.52×2
4
9
+7
5
9
×0.52.
分析:(1)根据乘法的交换律和结合律进行计算比较简便;
(2)根据乘法的分配律进行计算即可得到答案.
解答:解:①(0.4×0.8)×(2.5×12.5)
=(0.4×2.5)×(0.8×12.5)
=1×10
=10;
②0.52×2
4
9
+7
5
9
×0.52
=0.52×(2
4
9
+7
5
9

=0.52×10
=5.2.
点评:此题主要考查的是小数和分数的简便运算.
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