一个长方形的周长是24cm,长与宽的比为3:1,它的面积是 cm2.
0.75== ÷16=27: = %.
= : =33÷ = %
÷4=25%= : =8÷ = 折.
0.75= : = :25= 折= %= (成数)
10: ==0.625=5÷ = %