简算(78.6-0.786*25+0.75*21.4)/15*2003

(78.6-0.786*25+0.75*21.4)/15*2003 ={[78.6*(1-0.25)]+0.75*21.4}/15*2003 =(78.6*0.75+0.75*21.4)/15*2003 =[0.75*(78.6+21.4)]/15*2003 =(0.75*100)/15*2003 =75/15*2003 =5*2003 =10015