--- loncom/html/adm/help/tex/Statistics_Overall_Key.tex	2007/08/07 21:29:16	1.9
+++ loncom/html/adm/help/tex/Statistics_Overall_Key.tex	2008/02/22 19:22:21	1.10
@@ -77,7 +77,7 @@ problem parts of the selected students o
 
 To compute the KR-21 reliability statistic the following formula is used:
 
-\[KR-21 = \frac{K}{K-1} \cdot \frac{1-(M \cdot (K-M))}{K \cdot s^{2}}\]
+\[KR-21 = \frac{K}{K-1} \cdot \left(1- \frac{M \cdot (K-M)}{K \cdot s^{2}} \right)\]
 
 Where 
 \begin{description}