diff --git a/docs/lessons/speed-button/quiz.md b/docs/lessons/speed-button/quiz.md
index 51d303bc..0f8e7c39 100644
--- a/docs/lessons/speed-button/quiz.md
+++ b/docs/lessons/speed-button/quiz.md
@@ -37,7 +37,7 @@ input.onButtonPressed(Button.A, () => {
 ## 4. Draw which LED is ON after running this code and pressing Button A five times. Explain why you chose to draw that number.
 
 ```blocks
-count_ = 0
+let count_ = 0
 input.onButtonPressed(Button.A, () => {
     count_ = count_ + 1
     basic.showNumber(count_, 100)