1.78÷2.3= ÷23;37.8÷0.18= ÷18.
18÷ ==0.9:0.3=3: = :24.
÷15=0.8==16: = %= 折.
0.8==12÷ = 折= %
3÷ == :12=七成五= %
=0.75=15÷ .