diff --git a/functions.Rmd b/functions.Rmd
index 5a5dbdec..4b64c7aa 100644
--- a/functions.Rmd
+++ b/functions.Rmd
@@ -347,7 +347,7 @@ f3 <- function(x, y) {
 
 <div class="answer">
 
-The function `f1` tests whether each element of the character vector `nchar`
+The function `f1` tests whether each element of the character vector `string`
 starts with the string `prefix`. For example,
 ```{r}
 f1(c("abc", "abcde", "ad"), "ab")