It's true. 9 + 10 = 21. Listen to that famous meme again and again. and again. With this simple app, you will get to hear your favorite kid tell you the answer to 9+10. Don't like this app? Tell us why! Leave a review: ). Disclaimer #1: 9 + 10 ≠ 21. Duh. Disclaimer #2: It can get really annoying.