diff --git a/14_Day_Error_handling/14_day_error_handling.md b/14_Day_Error_handling/14_day_error_handling.md
index 696db4a..5a7cb8a 100644
--- a/14_Day_Error_handling/14_day_error_handling.md
+++ b/14_Day_Error_handling/14_day_error_handling.md
@@ -118,7 +118,7 @@ const throwErroExampleFun = () => {
   let x = prompt('Enter a number: ')
   try {
     if (x == '') throw 'empty'
-    if (isNaN(x)) throw 'not a number'
+    if (!Number.isFinite(x)) throw 'not a number'
     x = Number(x)
     if (x < 5) throw 'too low'
     if (x > 10) throw 'too high'