800X+400(10-X)+500(8-X)+300[6-(10-X)]=7600,
问题描述:
800X+400(10-X)+500(8-X)+300[6-(10-X)]=7600,
答
800X+400(10-X)+500(8-X)+300[6-(10-X)]=7600
800X+4000-400X+4000-500X+300(6-10+X)=7600
8000-100X-1200+300X=7600
200X=800
X=4