Question

0.25×1.25＋2.5×0.075简便方法运算

Answer 1

0.25×1.25＋2.5×0.075=0.25×1.25＋0.25×0.75=0.25×(1.25+0.75)=0.25×2=0.5

追问

我还是不懂 怎么都变成2.5了

追答

0.25=2.5×0.1
2.5=0.25×10
所以0.25×1.25＋2.5×0.075=0.25×1.25＋0.25×0.75
或者0.25×1.25＋2.5×0.075=2.5×0.125＋2.5×0.075

Answer 2

0.25*1.25+2.5*0.075
=2.5*0.125+2.5*0.075
=2.5*（0.125+0.075）
=2.5*0.2
=0.5

Answer 3

0.25×1.25＋2.5×0.075
=2.5×0.125＋2.5×0.075
=2.5×(0.125+0.075)
=2.5×0.2
=0.5