Question

2.84×7.9+2.84×2+28.4×0.01的简便计算？

Answer 1

2.84×7.9+2.84×2+28.4×0.01
=2.84×7.9+2.84×2+2.84×0.1
=2.84×(7.9+2+0.1)
=2.84×10
=28.4
首先，因为都有284这三个数字，所以把他们都化出2.84，然后再进行计算

Answer 2

这个题目可以采用乘法分配律的逆定理，我们可以把2.84提出来，又因为28.4＝2.84×10
2.84×7.9+2.84×2+28.4×0.01
＝2.84×7.9+2.84×2+2.84×0.01×10
＝2.84×（7.9+2+0.1）
＝2.84×10
＝28.4
所以这就是简便运算之后的结果是28.4。

Answer 3

2.84×7.9+2.84×2+28.4×0.01=2.84×7.9+2.84×2+2.84×10×0.01=2.84×（7.9+2+0.1）=2.84×10=28.4

Answer 4

根据乘法分配律的定律：先把最后一个乘法算式28.4×0.01改成2.84×0.1。本题=2.84×7.9+2.84×2+2.84×0.1=2.84*（7.9+2+0.1）=2.84×10=28.4

Answer 5

2.84×7.9+2.84×2+28.4×0.01=2.84×7.9+2.84×2+2.84×0.1=2.84×（7.9+2+0.1）=2.84×10=28.4