diff --git a/education/statistics/random-variable.html b/education/statistics/random-variable.html
index 65d4118..b952e2d 100644
--- a/education/statistics/random-variable.html
+++ b/education/statistics/random-variable.html
@@ -2,7 +2,7 @@
 title: 隨機變數 (Random Variable)
 description: 
 published: true
-date: 2025-12-28T16:48:42.180Z
+date: 2025-12-28T16:52:43.988Z
 tags: 
 editor: ckeditor
 dateCreated: 2025-12-28T16:41:51.938Z
@@ -10,11 +10,12 @@ dateCreated: 2025-12-28T16:41:51.938Z
 
 <h2><span style="font-family:Arial, Helvetica, sans-serif;">Discrete</span></h2>
 <h3><span style="font-family:Arial, Helvetica, sans-serif;">Probability Mass Function (PMF)</span></h3>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">A set of probability value <strong>p<sub>i</sub></strong> assigned to each of the values taken by the discrete random variables <strong>x<sub>i</sub></strong>.</span></p>
 <p>&nbsp;</p>
 <p>&nbsp;</p>
 <h3><span style="font-family:Arial, Helvetica, sans-serif;">Cumulative Distribution Function (CDF)</span></h3>
 <p>&nbsp;</p>
-<h2>Continuous</h2>
+<h2><span style="font-family:Arial, Helvetica, sans-serif;">Continuous</span></h2>
 <h3><span style="font-family:Arial, Helvetica, sans-serif;">Probability Density Function (PDF)</span></h3>
 <p>&nbsp;</p>
 <p>&nbsp;</p>