diff --git a/README.md b/README.md
index ed0e6c0..357c207 100644
--- a/README.md
+++ b/README.md
@@ -39,3 +39,4 @@
 53 * 82 = 4346
 52 + 9 = 61
 60 * 13 = 780
+73 - 80 = -7