①6x=18
②x:0.4=10:
③x﹣60%x=2
④=
(个)
问题:
解答:
5.2÷0.04= 1.32+0.8= 8 ÷8= 25+7.5=
51.51÷51= + ÷ = 1.5×2÷1.5×2= 149÷30≈