diff --git a/Chp4/Exercise_04_02.java b/Chp4/Exercise_04_02.java
index f1ec51b..cec8736 100644
--- a/Chp4/Exercise_04_02.java
+++ b/Chp4/Exercise_04_02.java
@@ -28,10 +28,10 @@ public static void main (String[] args){
 
         double d = 6371.01 * Math.acos((
             Math.sin(Math.toRadians(point_1_latitude)) *
-            Math.sin(Math.toRadians(point_1_longitude))) +
+            Math.sin(Math.toRadians(point_2_latitude))) +
             (Math.cos(Math.toRadians(point_1_latitude)) * 
-            Math.cos(Math.toRadians(point_1_longitude)) * 
-            Math.cos(Math.toRadians(point_2_longitude) - Math.toRadians(point_2_latitude))));
+            Math.cos(Math.toRadians(point_2_latitude)) * 
+            Math.cos(Math.toRadians(point_2_longitude) - Math.toRadians(point_1_longitude))));
     
         System.out.printf("The distance between the two points is %f km.%n", d);    
     }