diff --git a/extra/project-euler/006/006.factor b/extra/project-euler/006/006.factor
index 00a5c44771..c786c98c6c 100644
--- a/extra/project-euler/006/006.factor
+++ b/extra/project-euler/006/006.factor
@@ -15,7 +15,7 @@ IN: project-euler.006
 !    (1 + 2 + ... + 10)² = 55² = 3025
 
 ! Hence the difference between the sum of the squares of the first ten natural
-! numbers and the square of the sum is 3025 385 = 2640.
+! numbers and the square of the sum is 3025 - 385 = 2640.
 
 ! Find the difference between the sum of the squares of the first one hundred
 ! natural numbers and the square of the sum.