diff --git a/docs/enhance/net/neta.md b/docs/enhance/net/neta.md
index 042ea20f..d3ebd3fb 100644
--- a/docs/enhance/net/neta.md
+++ b/docs/enhance/net/neta.md
@@ -203,7 +203,7 @@ C ⊃ gateway
 
 192.168.1.3 && 255.255.255.192 = 192.168.1.0
 
-192.168.1.70 && 255.255.255.0 = 192.168.1.64
+192.168.1.70 && 255.255.255.192 = 192.168.1.64
 
 192.168.1.0 ≠ 192.168.1.64