48X28十48x74-48X2=48X(28十74-2)=48X100=4800
48X28十48x74-48X2=48x(28+74-2)=48x100=4800请采纳,谢谢
=48×(28+74-2)=48×100=4800
=48x(28+74-2)=48x100=4800