30000十3000十300十30十8一8=33330,根据后四个数每个加2凑整得整三万,三千,三百,三十,将多出8减去与加8为零,得到了33330。
巧算:8+28+298+2998+29998
29998+2998+298+28 =(30000-2)+(3000-2)+(300-2)+(30-2) =30000+3000+300+30-2-2-2-2 =33330-8 =33322
30000十3000十300十30十8一8=33330,根据后四个数每个加2凑整得整三万,三千,三百,三十,将多出8减去与加8为零,得到了33330。
巧算:8+28+298+2998+29998
29998+2998+298+28 =(30000-2)+(3000-2)+(300-2)+(30-2) =30000+3000+300+30-2-2-2-2 =33330-8 =33322