In this program, you’ll learn to calculate the average of the given arrays in Java.

1. Program to Calculate Average Using Arrays

public class Average {

    public static void main(String[] args) {
        double[] numArray = { 45.3, 67.5, -45.6, 20.34, 33.0, 45.6 };
        double sum = 0.0;

        for (double num: numArray) {
           sum += num;
        }

        double average = sum / numArray.length;
        System.out.format("The average is: %.2f", average);
    }
}

Output

The average is: 27.69

In the above program, numArray stores floating-point values whose average is to be found.

Then, to calculate the average, we must first compute the sum of all elements. This is done using the for-each loop in Java.

2. Program to find the average of numbers using array in Java

public class JavaExample {

    public static void main(String[] args) {
        double[] arr = {19, 12.89, 16.5, 200, 13.7};
        double total = 0;

        for(int i=0; i<arr.length; i++){
        	total = total + arr[i];
        }


        /* arr.length returns the number of elements 
         * present in the array
         */
        double average = total / arr.length;
        
        /* This is used for displaying the formatted output
         * if you give %.4f then the output would have 4 digits
         * after decimal point.
         */
        System.out.format("The average is: %.3f", average);
    }
}

Output:

The average is: 52.418

3. Calculate average of numbers entered by user

import java.util.Scanner;
public class JavaExample {

    public static void main(String[] args) {
        System.out.println("How many numbers you want to enter?");
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        /* Declaring array of n elements, the value
         * of n is provided by the user
         */
        double[] arr = new double[n];
        double total = 0;

        for(int i=0; i<arr.length; i++){
        	System.out.print("Enter Element No."+(i+1)+": ");
        	arr[i] = scanner.nextDouble();
        }
        scanner.close();
        for(int i=0; i<arr.length; i++){
        	total = total + arr[i];
        }


        
        double average = total / arr.length;
        
        System.out.format("The average is: %.3f", average);
    }
}

Output:

How many numbers you want to enter?
5
Enter Element No.1: 12.7
Enter Element No.2: 18.9
Enter Element No.3: 20
Enter Element No.4: 13.923
Enter Element No.5: 15.6
The average is: 16.225

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