diff --git a/app/src/main/java/com/xianwei/codecoveragetestapp/CalculatorViewModel.kt b/app/src/main/java/com/xianwei/codecoveragetestapp/CalculatorViewModel.kt
index cc03577..4ec6f3c 100644
--- a/app/src/main/java/com/xianwei/codecoveragetestapp/CalculatorViewModel.kt
+++ b/app/src/main/java/com/xianwei/codecoveragetestapp/CalculatorViewModel.kt
@@ -15,13 +15,11 @@ class CalculatorViewModel : ViewModel() {
         state.value = inputA - inputB
     }
 
-    fun onInputAUpdate(toString: String) {
-
+    fun onMultiplyClicked(inputA: Int, inputB: Int) {
+        state.value = inputA * inputB
     }
 
-    fun onInputBUpdate(toString: String) {
-
-
+    fun onDividerClicked(inputA: Int, inputB: Int) {
+        state.value = inputA / inputB
     }
-
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/xianwei/codecoveragetestapp/MainActivity.kt b/app/src/main/java/com/xianwei/codecoveragetestapp/MainActivity.kt
index 7851aaf..bc18dbf 100644
--- a/app/src/main/java/com/xianwei/codecoveragetestapp/MainActivity.kt
+++ b/app/src/main/java/com/xianwei/codecoveragetestapp/MainActivity.kt
@@ -42,9 +42,17 @@ class MainActivity : AppCompatActivity() {
         }
 
         binding.multiply.setOnClickListener {
+            if (validInput()) {
+                viewModel.onMultiplyClicked(inputA, inputB)
+                binding.sign.text = "*"
+            }
         }
 
         binding.divider.setOnClickListener {
+            if (validInput()) {
+                viewModel.onDividerClicked(inputA, inputB)
+                binding.sign.text = "/"
+            }
         }
     }
 
diff --git a/app/src/test/java/com/xianwei/codecoveragetestapp/CalculatorViewModelTest.kt b/app/src/test/java/com/xianwei/codecoveragetestapp/CalculatorViewModelTest.kt
index 07bc6e5..f573da9 100644
--- a/app/src/test/java/com/xianwei/codecoveragetestapp/CalculatorViewModelTest.kt
+++ b/app/src/test/java/com/xianwei/codecoveragetestapp/CalculatorViewModelTest.kt
@@ -32,4 +32,10 @@ class CalculatorViewModelTest {
         testViewModel.onPlusClicked(9, 2)
         assertEquals(11, testViewModel.state.value)
     }
+
+    @Test
+    fun test_on_minus_click_method() {
+        testViewModel.onMinusClicked(9, 2)
+        assertEquals(7, testViewModel.state.value)
+    }
 }
\ No newline at end of file