Average of N Numbers Example in Java

Introduction

Average of n numbers is a classic Java console program that demonstrates the concept with complete source code and sample output. Calculation programs apply formulas to solve geometry, statistics and numeric problems.

This tutorial walks through the program line by line, explains how the logic works, and highlights best practices you can apply in your own code.

Definition

An average is the sum of a list of numbers divided by the number of numbers in the list. In mathematics and statistics, this would be called the arithmetic mean.

Average of n numbers Example Program

import java.util.Scanner;
public class Average{
	public static void main(String[] args) {
		Scanner in= new Scanner(System.in); 
		System.out.print("Enter N number of elements " +"for finding average : ");
		final int count= in.nextInt();;
		System.out.println("");
		double[] numbers = new double[count];
		double sum = 0;
		for (int i = 0; i < count; i++) {
		System.out.print("Enter number "+(i+1)+" : " );
		numbers[i] = in.nextDouble();
		sum += numbers[i];
		}
    double avg = sum / count;
    System.out.println("");
    System.out.println("Average of the given numbers is " + avg);
	}
}

Sample Output

Enter N number of elements for finding average : 5

Enter number 1 : 45
Enter number 2 : 567
Enter number 3 : 7890
Enter number 4 : 345
Enter number 5 : 567

Average of the given numbers is 1882.8

When to use

Use these formulas in homework tools, engineering calculators or anywhere repeated numeric computation is needed.

How it works

1. Execution begins in the main method — the JVM calls this method when you run the class.

2. import java.util.Scanner; imports a class used later in the program.

3. A Scanner reads typed input from the keyboard (System.in).

4. A println / print call writes text to the console — part of the sample output below.

5. final int count= in.nextInt();; updates a variable used in the calculation or output.

6. A println / print call writes text to the console — part of the sample output below.

7. double[] numbers = new double[count]; updates a variable used in the calculation or output.

8. A println / print call writes text to the console — part of the sample output below.

Best Practices

• Use meaningful variable and class names that describe their purpose.
• Compile and run the program locally — modify values to see how output changes.
• Read compiler errors carefully; they usually point to the exact line to fix.

Common Mistakes

• Copying code without understanding each line — practice by changing one statement at a time.
• Mismatching the public class name and the .java filename.
• Forgetting semicolons at the end of statements.