“六一”儿童节的汇报演出经过2时30分,在21:50结束.演出是在 时 分开始.
=9÷ = :8== (填小数)
3: ==15÷ = ×= (小数).
5÷20==4: = :12= %= (填小数)
÷20=12: ==0.8= %.
= : =15÷ ==0.6.