2.3小时= 时 分,1.75立方分米= 升 毫升.
3÷ =6: ==0.75= %
3÷ = ÷24==75%= 折.
甲比乙少,乙与甲的比是4:5. .
÷12=1=12: = %
7÷9=,5÷7=.