75*4.67+19.9*2.5
问题描述：
75*4.67+19.9*2.5
答
75*4.67+19.9*2.5
=75*4+25*3*0.67+20*2.5-0.1*2.5
=300+25*2.01+20*2.5-25*0.01
=300+50+50
=400