diff --git a/subjects/notdecimal/README.md b/subjects/notdecimal/README.md
index f70e89607..4de84b168 100644
--- a/subjects/notdecimal/README.md
+++ b/subjects/notdecimal/README.md
@@ -10,7 +10,7 @@ Write a function called `Not_decimal()` that takes a float number with the decim
 ### Expected function
 
 ```go
-func Not_decimal(month float64) int {
+func Not_decimal(dec string) int {
 }
 ```
 ### Usage