Write a Program Average of Array in Java- Technology369kk

Average of Array

Program:

// Q6. WAP where use SUm of Average numbers

class ArrayArray{
    public static void main(String arg[]){
        // define an array
        int[] numbers = new int [] {10,20,30,40,50};

        // calculate sum of all array elements
        int sum =0; 
        
        for (int i= 0; i< numbers.length; i++){
            sum = sum + numbers[i];
        }

        // calculate average value
        double average = sum/numbers.length;

        System.out.println("Average value of array elements is:"+average);

    }
}

Explanation :

I am using in this program fast: - sum of natural numbers formal

The formula for the sum of the first $n$ natural numbers is:

Sn=n(n+1)/2

Explanation:

Natural numbers: These are the counting numbers starting from 1 (i.e., $1, 2, 3, \dots, n$ ).
Formula Derivation:

If we sum the first $n$ natural numbers: $S_n = 1 + 2 + 3 + \dots + n$
Pairing the terms from start and end: $(1 + n), (2 + (n-1)), (3 + (n-2)), \dots$ Each pair sums to $n+1$ , and there are $\frac{n}{2}$ pairs (if $n$ is even).
If $n$ is odd, the middle term will be unpaired, but the formula still holds.