Question

4.2×2.5÷4.2×2.5简便算法？

Answer 1

解：4.2×2.5÷4.2×2.5等于（ 25/4 ），【即等于6.25】
∵已知需求出4.2×2.5÷4.2×2.5等于多少
∴4.2 × 2.5 ÷ 4.2 × 2.5
= 4.2 × 2.5 × 1/4.2 × 2.5
= （4.2 × 1/4.2）× 2.5 × 2.5
= 1 × （2×10+5）/10 × （2×10+5）/10
= 1 × 25/10 × 25/10
= 1 × 5/2 × 5/2
= 5/2 × 5/2
= 25/4
= 6.25
答：4.2×2.5÷4.2×2.5等于25/4，【即等于6.25】

Answer 2

你好，这道题的简便算法如下：
4.2×2.5÷4.2×2.5
=4.2÷4.2×(2.5×2.5)
=1×1
=1
望采纳。

Answer 3

4.2×2.5÷4.2×2.5
移项
=4.2÷4.2×2.5×2.5
小数转化为分数计算
=1×5/2×5/2
=25/4
=25÷4
=6.25