public partial class Form1 : Form
    {
        Random randomNo = new Random();
        int no1;
        int no2;
        string problemType = "+";

        public Form1()
        {
            InitializeComponent();
        }

        private void StartGame_C1ick(object sender, EventArgs e)
        {
            StartGame.Visible = false;
            CheckAnswer.Visible = true;
            Question.Visible = true;
            Answer.Visible = true;
            NextQuestion.Visible = true;
            Feedback.Text = "";
            Feedback.Visible = true;
            Gen_Question();
        }

        private void Gen_Question()
        {
            no1 = randomNo.Next(100);
            no2 = randomNo.Next(100);

            if (radioButton1.Checked)
            {
                problemType = "+";
            }
            else if (radioButton2.Checked)
            {
                problemType = "-";
            }

            else if (radioButton3.Checked)
            {
                problemType = "*";
            }

            Question.Text = no1 + problemType + no2 + "=";
        }
        private void CheckAnswer_Click(object sender, EventArgs e)
        {
            int result = 0;
            if (problemType == "+")
            {
                result = no1 + no2;
            }
            else if (problemType == "-")
            {
                result = no1 - no2;
            }
            else if (problemType == "*")
            {
                result = no1 * no2;
            }

            if (Answer.Text == result.ToString())
            {
                Feedback.Text = "Correct";
            }
            else
            {
                Feedback.Text = "Incorrect";
            }

        }

        private void NextQuestion_Click(object sender, EventArgs e)
        {
            Gen_Question();

            Answer.Text = "";
            Feedback.Text = "";
        }

        public partial class Form1 : Form
        {
            Random randomNo = new Random();
            int no1;
            int no2;
            string problemType = "+";

            public Form1()
            {
                InitializeComponent();
            }

            private void StartGame_Click(object sender, EventArgs e)
            {
                StartGame.Visible = false;
                CheckAnswer.Visible = true;
                Question.Visible = true;
                Answer.Visible = true;
                NextQuestion.Visible = true;
                Feedback.Text = "";
                Feedback.Visible = true;
                Gen_Question();
            }

            private void Gen_Question()
            {
                no1 = randomNo.Next(100);
                no2 = randomNo.Next(100);

                if (radioButton1.Checked)
                {
                    problemType = "+";
                }
                else if (radioButton2.Checked)
                {
                    problemType = "-";
                }
                else if (radioButton3.Checked)
                {
                    problemType = "*";
                }

                Question.Text = no1 + problemType + no2 + "=";
            }

            private void CheckAnswer_Cl1ck(object sender, EventArgs e)
            {
                int result = 0;
                if (problemType == "+")
                {
                    result = no1 + no2;
                }
                else if (problemType == "-")
                {
                    result = no1 - no2;
                }
                else if (problemType == "*")
                {
                    result = no1 * no2;
                }

                if (Answer.Text == result.ToString())
                {
                    Feedback.Text = "Correct";
                }
                else
                {
                    Feedback.Text = "Incorrect";
                }
            }

            private void NextQuestion_C1ick(object sender, EventArgs e)
            {
                Gen_Question();
                Answer.Text = "";
                Feedback.Text = "";
            }
        }
    }
}

    public partial class Form1 : Form    {        Random randomNo = new Random();        int no1;        int no2;        string problemType = "+";        public Form1()        {            InitializeComponent();        }        private void StartGame_C1ick(object sender, EventArgs e)        {            StartGame.Visible = false;            CheckAnswer.Visible = true;            Question.Visible = true;            Answer.Visible = true;            NextQuestion.Visible = true;            Feedback.Text = "";            Feedback.Visible = true;            Gen_Question();        }        private void Gen_Question()        {            no1 = randomNo.Next(100);            no2 = randomNo.Next(100);            if (radioButton1.Checked)            {                problemType = "+";            }            else if (radioButton2.Checked)            {                problemType = "-";            }            else if (radioButton3.Checked)            {                problemType = "*";            }            Question.Text = no1 + problemType + no2 + "=";        }        private void CheckAnswer_Click(object sender, EventArgs e)        {            int result = 0;            if (problemType == "+")            {                result = no1 + no2;            }            else if (problemType == "-")            {                result = no1 - no2;            }            else if (problemType == "*")            {                result = no1 * no2;            }            if (Answer.Text == result.ToString())            {                Feedback.Text = "Correct";            }            else            {                Feedback.Text = "Incorrect";            }        }        private void NextQuestion_Click(object sender, EventArgs e)        {            Gen_Question();            Answer.Text = "";            Feedback.Text = "";        }        // Remove duplicate here.    }