diff --git a/Final/Final/Calculator.cs b/Final/Final/Calculator.cs
new file mode 100644
index 0000000..6a849bf
--- /dev/null
+++ b/Final/Final/Calculator.cs
@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Final
+{
+    public class Calculator
+    { 
+        public int Sum(int a, int b)
+        {
+            return a + b;
+        }
+        public int Sum(int a, int b, int c)
+        {
+            return a + b + c;
+        }
+        public double Sum(double a, double b)
+        {
+            return a + b;
+        }
+    }
+
+}
+
diff --git a/Final/Final/Form1.Designer.cs b/Final/Final/Form1.Designer.cs
index 0a6057a..d7090cf 100644
--- a/Final/Final/Form1.Designer.cs
+++ b/Final/Final/Form1.Designer.cs
@@ -46,12 +46,19 @@ namespace Final
             listBox2 = new ListBox();
             pictureBox1 = new PictureBox();
             tabPage3 = new TabPage();
+            w = new Label();
+            textBox6 = new TextBox();
+            textBox5 = new TextBox();
+            textBox4 = new TextBox();
+            button8 = new Button();
             colorDialog = new ColorDialog();
             colorDialog1 = new ColorDialog();
+            textBox2 = new TextBox();
             tabControl1.SuspendLayout();
             tabPage1.SuspendLayout();
             tabPage2.SuspendLayout();
             ((System.ComponentModel.ISupportInitialize)pictureBox1).BeginInit();
+            tabPage3.SuspendLayout();
             SuspendLayout();
             // 
             // tabControl1
@@ -211,6 +218,12 @@ namespace Final
             // 
             // tabPage3
             // 
+            tabPage3.Controls.Add(textBox2);
+            tabPage3.Controls.Add(w);
+            tabPage3.Controls.Add(textBox6);
+            tabPage3.Controls.Add(textBox5);
+            tabPage3.Controls.Add(textBox4);
+            tabPage3.Controls.Add(button8);
             tabPage3.Location = new Point(4, 34);
             tabPage3.Name = "tabPage3";
             tabPage3.Padding = new Padding(3);
@@ -219,6 +232,54 @@ namespace Final
             tabPage3.Text = "tabPage3";
             tabPage3.UseVisualStyleBackColor = true;
             // 
+            // w
+            // 
+            w.AutoSize = true;
+            w.Location = new Point(474, 462);
+            w.Name = "w";
+            w.Size = new Size(59, 25);
+            w.TabIndex = 9;
+            w.Text = "label1";
+            // 
+            // textBox6
+            // 
+            textBox6.Location = new Point(816, 152);
+            textBox6.Name = "textBox6";
+            textBox6.Size = new Size(150, 31);
+            textBox6.TabIndex = 8;
+            // 
+            // textBox5
+            // 
+            textBox5.Location = new Point(404, 152);
+            textBox5.Name = "textBox5";
+            textBox5.Size = new Size(150, 31);
+            textBox5.TabIndex = 7;
+            // 
+            // textBox4
+            // 
+            textBox4.Location = new Point(48, 152);
+            textBox4.Name = "textBox4";
+            textBox4.Size = new Size(150, 31);
+            textBox4.TabIndex = 6;
+            textBox4.TextChanged += textBox4_TextChanged;
+            // 
+            // button8
+            // 
+            button8.Location = new Point(454, 324);
+            button8.Name = "button8";
+            button8.Size = new Size(112, 34);
+            button8.TabIndex = 1;
+            button8.Text = "button8";
+            button8.UseVisualStyleBackColor = true;
+            button8.Click += button8_Click;
+            // 
+            // textBox2
+            // 
+            textBox2.Location = new Point(610, 456);
+            textBox2.Name = "textBox2";
+            textBox2.Size = new Size(150, 31);
+            textBox2.TabIndex = 10;
+            // 
             // Form1
             // 
             AutoScaleDimensions = new SizeF(10F, 25F);
@@ -233,6 +294,8 @@ namespace Final
             tabPage2.ResumeLayout(false);
             tabPage2.PerformLayout();
             ((System.ComponentModel.ISupportInitialize)pictureBox1).EndInit();
+            tabPage3.ResumeLayout(false);
+            tabPage3.PerformLayout();
             ResumeLayout(false);
         }
 
@@ -256,5 +319,11 @@ namespace Final
         private Button button6;
         private Label l;
         private ColorDialog colorDialog1;
+        private TextBox textBox6;
+        private TextBox textBox5;
+        private TextBox textBox4;
+        private Button button8;
+        private Label w;
+        private TextBox textBox2;
     }
 }
\ No newline at end of file
diff --git a/Final/Final/Form1.cs b/Final/Final/Form1.cs
index 80c1985..7776675 100644
--- a/Final/Final/Form1.cs
+++ b/Final/Final/Form1.cs
@@ -1,5 +1,6 @@
 using System.Drawing;
 using System.Windows.Forms;
+using static System.Windows.Forms.VisualStyles.VisualStyleElement;
 using static System.Windows.Forms.VisualStyles.VisualStyleElement.Rebar;
 
 namespace Final
@@ -60,7 +61,7 @@ namespace Final
                 Point position = new Point(rand.Next(0, pictureBox1.Width - width), rand.Next(0, pictureBox1.Height - height));
                 RectangleWithOval rectangleWithOval = new RectangleWithOval(width, height, position, selectedColor);
                 rectangles.Add(rectangleWithOval);
-                listBox1.Items.Add(rectangleWithOval);
+                listBox2.Items.Add(rectangleWithOval);
             }
             else
             {
@@ -118,6 +119,46 @@ namespace Final
                 }
             }
         }
+
+        private void textBox4_TextChanged(object sender, EventArgs e)
+        {
+        }
+
+        private void button7_Click(object sender, EventArgs e)
+        {
+
+
+        }
+
+        private void button8_Click(object sender, EventArgs e)
+        {
+            Calculator calculator = new Calculator();
+
+            if (int.TryParse(textBox4.Text, out int number1) &&
+                int.TryParse(textBox5.Text, out int number2))
+            {
+                if (int.TryParse(textBox6.Text, out int number3))
+                {
+                    int result = calculator.Sum(number1, number2, number3);
+                    textBox2.Text = $"Sum: {result}";
+                }
+                else
+                {
+                    int result = calculator.Sum(number1, number2);
+                    textBox2.Text = $"Sum: {result}";
+                }
+            }
+            else if (double.TryParse(textBox4.Text, out double doubleNumber1) &&
+                 double.TryParse(textBox5.Text, out double doubleNumber2))
+            {
+                double result = calculator.Sum(doubleNumber1, doubleNumber2);
+                textBox2.Text = $"Sum (double): {result}";
+            }
+            else
+            {
+                textBox2.Text = "Invalid input";
+            }
+        }
     }