diff --git a/lib/calculator_brain.dart b/lib/calculator_brain.dart
index 5783edd..99dc0e4 100644
--- a/lib/calculator_brain.dart
+++ b/lib/calculator_brain.dart
@@ -1,12 +1,17 @@
 import 'dart:math';
+import 'package:bmi_calculator/screens/input_page.dart';
+import 'package:flutter/cupertino.dart';
 
 class CalculatorBrain {
-  CalculatorBrain({this.height, this.weight});
-
+  CalculatorBrain({@required this.weight,@required this.height,@required this.age,@required this.gender});
   final int height;
   final int weight;
-
+  final int age;
+  final Gender gender;
   double _bmi;
+  //start values for 25-34 male
+  double _overweight = 25.0;
+  double _underweight = 20;
 
   String calculateBMI() {
     _bmi = weight / pow(height / 100, 2);
@@ -14,9 +19,34 @@ class CalculatorBrain {
   }
 
   String getResult() {
-    if (_bmi >= 25) {
+    //Gender Check
+    if (gender == Gender.female) {
+      _overweight--;
+      _underweight--;
+    }
+
+    //Age Check
+    if (age <= 24) {
+      _overweight--;
+      _underweight--;
+      // 25 -34 is the normal Rate
+    } else if (age >= 35 && age <= 44) {
+      _overweight++;
+      _underweight++;
+    } else if (age >= 45 && age <= 54) {
+      _overweight = _overweight + 2;
+      _underweight = _underweight + 2;
+    } else if (age >= 55 && age <= 64) {
+      _overweight = _overweight + 3;
+      _underweight = _underweight + 3;
+    } else if (age > 64) {
+      _overweight = _overweight + 4;
+      _underweight = _underweight + 4;
+    }
+
+    if (_bmi >= _overweight) {
       return 'Overweight';
-    } else if (_bmi > 18.5) {
+    } else if (_bmi > _underweight) {
       return 'Normal';
     } else {
       return 'Underweight';
@@ -24,9 +54,9 @@ class CalculatorBrain {
   }
 
   String getInterpretation() {
-    if (_bmi >= 25) {
+    if (_bmi >= _overweight) {
       return 'You have a higher than normal body weight. Try to exercise more.';
-    } else if (_bmi >= 18.5) {
+    } else if (_bmi > _underweight) {
       return 'You have a normal body weight. Good job!';
     } else {
       return 'You have a lower than normal body weight. You can eat a bit more.';
diff --git a/lib/screens/input_page.dart b/lib/screens/input_page.dart
index d3da204..25d28d9 100644
--- a/lib/screens/input_page.dart
+++ b/lib/screens/input_page.dart
@@ -212,25 +212,36 @@ class _InputPageState extends State<InputPage> {
             ),
           ),
           BottomButton(
-            buttonTitle: 'CALCULATE',
-            onTap: () {
-              CalculatorBrain calc =
-                  CalculatorBrain(height: height, weight: weight);
+              buttonTile: 'CALCULATE',
+              onTap: () {
+                if (selectedGender == null){
+                  Alert(
+                      style: AlertStyle(
+                        backgroundColor: Color(0xFF1D1E33),
+                        titleStyle: kLargeButtonText,
 
-              Navigator.push(
-                context,
-                MaterialPageRoute(
-                  builder: (context) => ResultsPage(
-                        bmiResult: calc.calculateBMI(),
-                        resultText: calc.getResult(),
-                        interpretation: calc.getInterpretation(),
                       ),
-                ),
-              );
-            },
-          ),
-        ],
-      ),
+                      context: context,
+                      title: 'Please select Gender.',
+                    ).show();
+
+                }
+                else {
+                  CalculatorBrain calc = CalculatorBrain(height: height,
+                      weight: weight,
+                      age: age,
+                      gender: selectedGender);
+
+                  Navigator.push(context,
+                      MaterialPageRoute(builder: (context) => ResultPage(bmiResult: calc.calculateBMI(),resultText: calc.getResult(),interpretation: calc.getInterpretation(),)));
+
+                }
+                //print(selectedGender);
+
+                },
+            )
+          ],
+        ),
     );
   }
 }
diff --git a/pubspec.yaml b/pubspec.yaml
index 6dded66..039f113 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -11,7 +11,8 @@ dependencies:
     sdk: flutter
 
   cupertino_icons: ^0.1.2
-  font_awesome_flutter: ^8.4.0
+  font_awesome_flutter: ^9.0.0
+  rflutter_alert: ^2.0.2
 
 dev_dependencies:
   flutter_test: