3.5÷0.7= 0.72÷0.2 = 3.6÷12=
2÷9=0.222…,2÷99=0.0202…,2÷999=0.002002…,2÷9999=
36x+a=,b+0.24=
(m×n)×12=×(×)
=10×1.2
=12
=8×12.5+0.4×5
=100+2
=102
A. B. C.
①
②
③
平方米