# Average of first n even natural numbers?

CServer Side ProgrammingProgramming

Average or mean of n even natural number is the sum of numbers divided by the numbers.

You can calculate this by two methods &minus

• Find the sum of n even natural numbers and divide it by number, Using loop.

• Find the sum of n even natural numbers and divide it by number, Using formula.

## Method 1 - Using Loop

Find the sum of even natural numbers using a loop that counts up to the number we want the sum. Then we will divide it by n.

## Example Code

Live Demo

#include <stdio.h>
int main(void) {
int n = 5;
int sum = 0;
int average = 0;
for (int i = 1; i <= n ; i++) {
sum += (i*2);
}
average = sum / n;
printf("The average of %d even natural numbers is %d", n,average);
return 0;
}

## Output

The average of 5 even natural numbers is 6

## Method 1 − Using Formula

Find the sum of even natural numbers using a mathematical Formula that directly calculates the average.

The formula is (n + 1) = n*(n + 1 )/ n..

## Example Code

Live Demo

#include <stdio.h>
int main(void) {
int n = 5;
int average = n+1 ;
printf("The average of %d even natural numbers is %d", n,average);
return 0;
}

## Output

The average of 5 even natural numbers is 6

The second method that uses formula is better because in cases with larger value of n, the loop will run n time will increase the time.

Published on 15-Jul-2019 15:28:07