最大的两位数与最小的两位数的积是 ,和是 .
=15÷ = :50=.
1.5: =0.75=75÷ = :36=.
:12=5÷4== %= (填小数).
3÷4=9: == 填分数= (填小写)
9: =0.75==21÷ = :4.