diff --git a/exercises/06_move_semantics/move_semantics4.rs b/exercises/06_move_semantics/move_semantics4.rs
index 83a0344..56da988 100644
--- a/exercises/06_move_semantics/move_semantics4.rs
+++ b/exercises/06_move_semantics/move_semantics4.rs
@@ -8,11 +8,11 @@ mod tests {
     // Don't add, change or remove any line.
     #[test]
     fn move_semantics4() {
-        let mut x = 100;
+        let mut x = Vec::new();
         let y = &mut x;
         let z = &mut x;
-        *y += 100;
-        *z += 1000;
-        assert_eq!(x, 1200);
+        y.push(42);
+        z.push(13);
+        assert_eq!(x, [42, 13]);
     }
 }
diff --git a/solutions/06_move_semantics/move_semantics4.rs b/solutions/06_move_semantics/move_semantics4.rs
index b7919ac..64fdd9d 100644
--- a/solutions/06_move_semantics/move_semantics4.rs
+++ b/solutions/06_move_semantics/move_semantics4.rs
@@ -7,15 +7,15 @@ mod tests {
     // TODO: Fix the compiler errors only by reordering the lines in the test.
     // Don't add, change or remove any line.
     #[test]
-    fn move_semantics5() {
-        let mut x = 100;
+    fn move_semantics4() {
+        let mut x = Vec::new();
         let y = &mut x;
         // `y` used here.
-        *y += 100;
+        y.push(42);
         // The mutable reference `y` is not used anymore,
         // therefore a new reference can be created.
         let z = &mut x;
-        *z += 1000;
-        assert_eq!(x, 1200);
+        z.push(13);
+        assert_eq!(x, [42, 13]);
     }
 }