分出一半。○○○○○○○○○○○○○○( )=( )+( )
n÷n=. .
= ÷8=1.25=5: = %
= ÷5=0.8=4: = %= 折.
==12÷ = (小数)
16: == ÷5= %= (填小数)=八折.