简便计算(0.2×20+1.5)+(0.2×19+1.5)+(0.2×18+1.5)+…+(0.2×11+1.5)

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/10 07:40:44

简便计算(0.2×20+1.5)+(0.2×19+1.5)+(0.2×18+1.5)+…+(0.2×11+1.5)
简便计算(0.2×20+1.5)+(0.2×19+1.5)+(0.2×18+1.5)+…+(0.2×11+1.5)

简便计算(0.2×20+1.5)+(0.2×19+1.5)+(0.2×18+1.5)+…+(0.2×11+1.5)
=0.2x(20+30x4+15)+1.5x10
=0.2x155+1.5x10
=31+15
=46