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Co-authored-by: Copilot <[email protected]>

Author: clairernovotny

src/Humanizer/Localisation/NumberToWords/CatalanNumberToWordsConverter.cs

@@ -181,7 +181,8 @@ private string GetOrdinalTens(int number, GrammaticalGender gender)
             {
                 var tensDec = tens[dec];
                 if (dec == 3 || dec == 6 || dec == 7 || dec == 8 || dec == 9)
-                    tensDec = tensDec.Substring(0, tensDec.Length - 1); //
+                    // Remove the trailing 'a' from the tens word before adding the ordinal suffix (e.g., "trenta" -> "trentè")
+                    tensDec = tensDec.Substring(0, tensDec.Length - 1);
 
                 return tensDec + ordSuf;
             }