diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 049546a6..2ab785ba 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -23,7 +23,7 @@ are a good place to start.
 
 You can also check the [``help wanted``](https://github.com/Microsoft/calculator/labels/help%20wanted) tag to find 
 other issues to help with. If you're interested in working on a fix, leave a comment to let everyone know and to help
- avoid duplicated effort from others.
+avoid duplicated effort from others.
 
 ## Contributions we accept
 We welcome your contributions to the Calculator project, especially to fix bugs and to make