两个因数相乘,一个因数扩大3倍,另一个因数扩大4倍,积 .
=0.75== : = %
= : =75%=3÷ = .(填小数)
10÷ = :75== %= (填小数).
÷4=2=3=.
÷ = %=0.375=.