3× = ÷2= × = ÷ = 0.6÷ =
6÷ = ×1.5= -0.2= ÷0.25= 0.45÷ =
①1- ÷2.5
② ×(15- )
③ ÷( + )
④3-1÷ ×
⑤2-1.5× +
⑥0.12÷ +0.13×
升=毫升 90分钟=小时
(小数)=35%=
252=(20+5)2=202+52+