diff --git a/02-intro2R.Rmd b/02-intro2R.Rmd
index 24a015d..e8dbea6 100644
--- a/02-intro2R.Rmd
+++ b/02-intro2R.Rmd
@@ -230,7 +230,7 @@ x<-c(1,2,3,4)
 y<-c(4,5,6,7)
 m1<-cbind(x,y);m1
 t(m1)                # transpose of m1
-dim(m1)              # 2 by 5 matrix
+dim(m1)              # 2 by 4 matrix
 ```
 You can also directly list the elements and specify the matrix:
 ```{r matrix2}