12.5×(20+0.8)=12.5×20+12.5×0.8=250+10=260
12.5*(20+0.8)=12.5*20+12.5*0.8=250+10=260
12.5×(20+0.8)=12.5×20+12.5×0.8=250+12.5×(1-0.2)=250+12.5-2.5=260