diff --git a/README.md b/README.md
index 818c791..d3fe2ea 100644
--- a/README.md
+++ b/README.md
@@ -41,3 +41,4 @@
 64 * 11 = 704
 83 + 17 = 100
 37 - 58 = -21
+12 - 91 = -79