口算下面各题.36÷9= 81÷3=100÷5= 360÷90=810÷30= 1000÷50=3600÷900= 8100÷300=10000÷500=
99+11×19+11×80 .
123×5.67+8.77×567= .
80×16×25×125= .
(562×397)÷(281×397)= .
29×12+29×13+29×25+29×10= .