diff --git a/README.md b/README.md
index 61b0f61..0e4d278 100644
--- a/README.md
+++ b/README.md
@@ -278,7 +278,7 @@ for i in range(10):
 ```python
 map(lambda x: x+1, range(10))     # [1, 2, ..., 10]
 filter(lambda x: x>5, range(10))  # [6, 7, ..., 9]
-functools.reduce(combining_function, list_of_inputs)
+functools.reduce(lambda sum, x: sum+x, range(10))  # 45
 ```
 
 ### Any, All