从放有7个红球3个白球的袋子中摸球.那么, 色球摸到的可能性大.
40: =8:10= /5= (填小数)
=18: = ÷40= [填小数].
==10÷ = ÷36.
:16= ÷ ==0.125.
a÷b=,那么=. .