diff --git a/问题/均贫富.md b/问题/均贫富.md
index a50e6ea..62deba3 100644
--- a/问题/均贫富.md
+++ b/问题/均贫富.md
@@ -20,4 +20,4 @@ $
 
 ## 解法2
 
-$ x = \frac{a+b}{2} - b $
+$ x = \dfrac{a+b}{2} - b $