Output in one window Can anyone give me feedback please? I used what I have learnt so far, mainly methods, loops and arrays. I would like you view based on these topics, however, comments on how to improve are welcome. 

/*ask the user for 10 numbers
store them in an array
print them "your numbers are:"
print them "Average"
print them "Max"
print them "Min"*/

import javax.swing.*;

public class homeworkArrayWFunctionstest5
{
    public static void main(String[] args) throws Exception
    {
        String listOfNums = "";
        int sum = 0;
        int population = 0;
        int average = 0;
        int maxValue = 0;
        int minValue = 0;
        String [] numsStringInput = new String[10];
        population = numsStringInput.length;
        int [] arrayNumInt = new int[population];

        numsStringInput     = UserInputs(numsStringInput,population);
        arrayNumInt         = StringToInt(numsStringInput,population);
        listOfNums          = OneLineList(numsStringInput, population);
        sum                 = TotalCalc(arrayNumInt,population);
        average             = AvarageCalc(sum, population);
        maxValue            = MaxValueCalc(arrayNumInt,population);
        minValue            = MinValueCalc(arrayNumInt,population);

        Output(listOfNums,average,minValue,maxValue);
    }

    public static String [] UserInputs(String []numsStringInput,int population)
    {
        for (int i = 0; i&lt;population; i++)
        {
            numsStringInput [i] = JOptionPane.showInputDialog(null,"Please Input number " + (i+1) + " of " + population + " numbers","Input Table",JOptionPane.QUESTION_MESSAGE);
        }

        return numsStringInput;
    }

    public static int [] StringToInt(String[] numsStringInput,int population)
    {
        int [] arrayNumInt = new int[population];

        for (int i = 0; i&lt;population; i++)
        {
            arrayNumInt [i] = Integer.parseInt(numsStringInput [i]);
        }
        return arrayNumInt;
    }

    public static String OneLineList(String[] numsStringInput,int population)
    {
        String listOfNums = "";
        for (int i = 0; i&lt;population; i++)
            {
                listOfNums = listOfNums + numsStringInput [i] + " ";
            }

        return listOfNums;
    }

    public static int TotalCalc(int []arrayNumInt,int population)
    {
        int total = 0;
        for(int i=0;i &lt; population;i++)
        {
            total = total + arrayNumInt[i];
        }
        return total;
    }

    public static int AvarageCalc(int sum,int population)
    {
        int avarage = sum / population;
        return avarage;
    }

    public static int MaxValueCalc(int []arrayNumInt,int population)
    {
        int maxValue = arrayNumInt[0];
        for(int i=1;i &lt; population;i++)
        {
            if(arrayNumInt[i] &gt; maxValue)
            {
              maxValue = arrayNumInt[i];
            }
        }
        return maxValue;
    }

    public static int MinValueCalc(int []arrayNumInt,int population)
    {
        int minValue = arrayNumInt[0];
        for(int i=1;i &lt; population;i++)
        {
            if(arrayNumInt[i] &lt; minValue)
            {
              minValue = arrayNumInt[i];
            }
        }
        return minValue;
    }

    public static void Output(String listOfNums, int average, int minValue,int maxValue )
    {
        String text = "";

        String messageText[] = new String [] {"The number you have entered are:","Average is: ","Minimum number is: ","Maximum number is: "};
        int [] textNum = new int[] {0,average,minValue,maxValue};

        text = messageText[0]+ "\n" + listOfNums;

        for (int i = 1; i&lt;messageText.length; i++)
        {
            text = text + "\n" + messageText[i] + textNum[i];
        }
        JOptionPane.showMessageDialog(null,text,"Output Table" ,JOptionPane.INFORMATION_MESSAGE);
    }
}
The Java standard dictates the use of the "Egyptian braces" style:

if (something) {
    // something...
}

In AvarageCalc():


int avarage = sum / population;
return avarage;



you can just return the calculation:

return sum / population;


Also, it should be spelled average. ;-)
In Output(), you don't need to declare text and then assign it later.  Instead, initialize it where it's first used.  Always try to keep variables as close in scope as possible, which can help keep your code cleaner and easier to maintain.

String text = messageText[0]+ "\n" + listOfNums;