diff --git a/README.md b/README.md
index 71d345c..29f5f4d 100644
--- a/README.md
+++ b/README.md
@@ -41,3 +41,4 @@
 40 / 3 = 13
 22 + 67 = 89
 95 + 33 = 128
+23 - 1 = 22