加工一批零件,甲要6小时,乙要10小时,甲乙两人的工效的比是3:5. .
15÷ = :16=0.125== %.
12÷ == :80= %
4÷ =0.8== :40= %= 成.
15: ==0.75= %=6÷ .
÷8==0.5= :24.