某次数学测验甲、乙、丙的成绩为:82分,67分,91分,他们的平均成绩为 分.
3÷4==27: = (填小数)= %.
÷4==0.25= :8.
=9÷ = :8== (填小数)
3: ==15÷ = ×= (小数).
5÷20==4: = :12= %= (填小数)