**In this post students will be able to learn how to find the sum and average of first n natural number using C Programming Language.**

Page Contents

#### Write a program to find sum and average of first n natural number.

*Program:*

*Program:*

```
#include<stdio.h>
int main(){
int n,i,sum=0;
float average;
printf("Enter a positive integer n: ");
scanf("%d", &n);
for (i = 1; i <= n; i++) {
sum += i;
}
average = (float)sum / n;
printf("The sum of the first %d natural numbers is %d\n", n, sum);
printf("The average of the first %d natural numbers is %.2f\n", n, average);
return 0;
}
```

*Explaination:*

*Explaination:*

- The user is prompted to enter a positive integer n using the
`printf()`

function and the`scanf()`

function is used to read the user input and store it in the variable`n`

. - A variable called
`sum`

is initialized to 0. - A
`for`

loop is used to iterate from 1 to n (inclusive). For each iteration, the loop adds the current number (i) to the`sum`

variable. - Once the loop is finished, the average is calculated by dividing the sum by n and storing the result in a variable called
`average`

. Note that we cast`sum`

to a float before dividing by`n`

to ensure that the result is a floating-point number. - The sum and average are printed to the console using the
`printf()`

function.