怎样简便计算 (10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/06 00:42:01

怎样简便计算 (10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)
怎样简便计算 (10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)

怎样简便计算 (10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)
(10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)
=(10+9+8+7+...+1)-7/55*(1+2+3+4+...+10)(去括号合并同类项)
=55-7/55*55(我不知道你是那个年级的,1到10的连加不说明)
=55-7
=48

(10-7/55*1)+(9-7/55*2)+(8-7/55*3)+······+(1-7/55*10)
=(10+1)*10/2-7/55(1+2+3+……+10)
=55-7/55*55
=48