170﹣90=
0.46+0.4=
0.56÷0.8=
5.4÷0.09= 7.75+3.86-7.75+1.14= 2.5×0.99×0.4=
26.2+38= 40×0.1÷0.001= 56.27- 3.73-46.27=
19﹣1.7= 2.4÷0.04= 496+298= ×0.2=
9.7+0.03= ÷1.75= 1×÷= +÷+=
1-0.92= - = ×3.2= ÷ ×5=
3.5+4.28= × = ÷ = 99×0.9+0.9=
5升30毫升=升 3.05千克=克
公顷=平方米 2时20分=时