做乘法时,哪一位上乘得的积满几十,就向 位进几.
=l8: = :20== ÷40= (填小数)
3:8=18÷ ═ %= .小数.
÷8===15÷ = ÷32= (填小数)
0.3==12÷ = :30= %
÷40=20: =0.8= : .