236.28+3.72=简算46.29.98=简算

23-6.28+3.72= 简算 46.2-9.98=简算 -
23-6.28+3.72 =23-6+3+（0.72-0.28）20=0.44 =19.56 46.2-9.98=46-10+0.2+0.02=36.22