摘要： 课后习题： x1 = c(13,15,16,16,19,20,20,21,22,22,25,25,25,25,30,33,33,35,35,35,35,36,40,45,46,52,70); print(round(mean(x1))); #平均值 print(median(x1,na.rm=TRUE)); #中值 阅读全文