diff --git a/chapters/part1/prob_or/index.html b/chapters/part1/prob_or/index.html
index 402441a8..18d4653a 100644
--- a/chapters/part1/prob_or/index.html
+++ b/chapters/part1/prob_or/index.html
@@ -89,7 +89,7 @@ <h2><b>Or</b> with Non-Mutually Exclusive Events</h2>
 <h2>Inclusion-Exclusion with Three Events</h2>
 
 <p>What does the inclusion exclusion property look like if we have three events, that are not mutually exclusive, and we want to know the probability of or, $
-	\P(E_1 \or \E_2 \or E_3)?
+	\P(E_1 \or E_2 \or E_3)?
 	$</p>
 
 
@@ -98,7 +98,7 @@ <h2>Inclusion-Exclusion with Three Events</h2>
 
 $$
 \begin{aligned}
-\P(E_1 &\or \E_2 \or E_3) = \\
+\P(E_1 &\or E_2 \or E_3) = \\
 & + \P(E_1) \\
 &+ \P(E_2) \\
 &+ \P(E_3) \\