diff --git a/README.md b/README.md
index 97b0bcc..6f929d2 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,6 @@
 57 / 9 = 6
 36 + 75 = 111
 72 / 8 = 9
-11 - 20 = -9
 11 + 17 = 28
 53 / 3 = 17
 60 - 21 = 39