Question

2.5×1.7+0.25×29－2.5×0.6简便运算？

Answer 1

因为0.25×29=2.5×2.9，所以原式等于2.5×1.7+2.5×2.9-2.5×0.6，运用乘法分配律逆运算可以得到2.5×（1.7+2.9-0.6）=10

Answer 2

根据题意把相同都数提出来运用结合律，同时把0.25×29看做2.5×2.9就可以得到
2.5×（1.7+2.9-0.6）
＝2.5×4
＝10

Answer 3

根据乘法分配律，得
原式=0.25×17+0.25×29-0.25×6
=0.25×(17+29-6)
=0.25×40
=10

Answer 4

2.5x1.7十0.25x29一2.5x0.6
=2.5x1.7十2.5x2.9一2.5x0.6
=2.5x(1.7+2.9一0.6)
=2.5x4=10

Answer 5

2/9×1/4×0.25-7/9×25%=2/9×1/4×1/4-7/9×1/4=(2/9×1/4-7/9)×1/4=(1/18-7/9)×1/4=-13/18×1/4=-13/72