把3米长的绳子平均分成5份,每份占全长的 ,每份长有 米.
1﹣1× =0 ÷ == : =75%
: =0.125= %==.
9÷ == :8=0.75= %= 折.
=0.375= ÷24= %
:20==0.8=12÷ = %.