diff --git a/docs/lessons/headbands/quiz-answers.md b/docs/lessons/headbands/quiz-answers.md
index 697cbec7..7d0ed86c 100644
--- a/docs/lessons/headbands/quiz-answers.md
+++ b/docs/lessons/headbands/quiz-answers.md
@@ -73,6 +73,7 @@ coll.push("cow")
 <br/>
 
 ```blocks
+let coll: string[] = []
 let index = Math.random(coll.length)
 let word = coll[index]
 ```