上式=84×1.375+4/19×1.375+105×0.9+5/19×0.9 =115.5+94.5+4/19×1.375+5/19×0.9 =210+(4/19+5/19)×0.9+4/19×0.475 =210+9/19×0.9+4/19×19/40 =210+81/190+1/10 =210+10/19 =210又19分之10 不好意思,几又几分之几不好打
用计算器吧,简单快捷