diff --git a/subjects/not_decimal/README.md b/subjects/not_decimal/README.md
index b6bb78898..f36e1f12b 100644
--- a/subjects/not_decimal/README.md
+++ b/subjects/not_decimal/README.md
@@ -12,7 +12,7 @@ Write a function called `Not_decimal()` that takes a string in forme of a float
 ### Expected function
 
 ```go
-func Not_decimal(dec string) int {
+func Not_decimal(dec string) string {
 }
 ```
 ### Usage