My programs print statement is wrong

When i run my program and choose a number between 0 and 100, it prints my answer wrong.

Java console

 ----jGRASP exec: java TestScores

How many tests do you have? 3
Enter grade for Test 1: 80
Enter grade for Test 2: 80
Enter grade for Test 3: 80
The average is: 26.666666666666668The average is: 53.333333333333336The average is: 80.0
 ----jGRASP: operation complete.

import java.util.Scanner;

public class TestScores {

    public static void main(String[] args)
    {
        int numTests = 0;
        double[] grade = new double[numTests];
        double totGrades = 0;
        double average;
        int check = 1;

        Scanner keyboard = new Scanner(System.in);
        System.out.print("How many tests do you have? ");
        numTests = keyboard.nextInt();
        grade = new dou开发者_运维技巧ble[(int) numTests];

        for (int index = 0; index < grade.length; index++)
        {
            System.out.print("Enter grade for Test " + (index + 1) + ": ");
            grade[index] = keyboard.nextDouble();

            if (grade[index] < 0 || grade[index] > 100)
            {
                try
                {
                    throw new InvalidTestScore();
                } 
                catch (InvalidTestScore e)
                {
                    e.printStackTrace();
                }
                break;
            }
        }

        for (int index = 0; index < grade.length; index++) {
            totGrades += grade[index];
            average = totGrades / grade.length;
            System.out.print("The average is: " + average);
        }
    }
}

public class InvalidTestScore extends Exception 
{
    public InvalidTestScore() 
    {
        super(" Error: Enter a number between 0 and 100");
    }
}

You print the average inside the loop that calculates the average.

Print it only outside the loop.

You should calculate sum in loop and then (after the loop) divide it by the number of elements.

I move the statement which calculates the sum from inside the loop to the outside, that works.

My new code is.

import java.util.Scanner;

public class TestScores

{

    public static void main(String[]args)

    {

            int numTests = 0;

            double[] grade = new double[numTests];

            double totGrades = 0;

            double average;

                 int check = 1;


            Scanner keyboard = new Scanner(System.in);


            System.out.print("How many tests do you have? ");

            numTests = keyboard.nextInt();



            grade = new double[(int) numTests];



            for (int index = 0; index < grade.length; index++)

            {

                    System.out.print("Enter grade for Test " + (index + 1) + ": ");

                    grade[index] = keyboard.nextDouble();


                    if (grade[index] < 0 || grade[index]> 100)

                    {
                                    try 

                                      {

                                throw new InvalidTestScore();


                            }

                                       catch (InvalidTestScore e) 

                            {

                                    e.printStackTrace();

                            }
                                        break;

                    }

            }

                for (int index = 0; index < grade.length; index++)
                 {  
                        totGrades += grade[index];



              }

                  average = totGrades/grade.length;


                  System.out.print("The average is: " + average);

    }

}

public class InvalidTestScore extends Exception { public InvalidTestScore() { super(" Error: Enter a number between 0 and 100"); } }

You can close my post.