400×40的积的末尾有 个0;60×50积的末尾有 个0.
:8==0.875= ÷24= %
=2:5=18÷ = %= (填小数)
:5=0.8== ÷20= %
0.4==16÷ = :10= %
: = =1.25=125÷ .