diff --git a/mysql/weather-observation-station-4/solution.sql b/mysql/weather-observation-station-4/solution.sql
new file mode 100644
index 0000000..6bb51e2
--- /dev/null
+++ b/mysql/weather-observation-station-4/solution.sql
@@ -0,0 +1,2 @@
+SELECT COUNT(CITY) - COUNT(DISTINCT CITY)
+FROM STATION
\ No newline at end of file