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

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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.

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

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:

1. 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.
2. A variable called sum is initialized to 0.
3. 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.
4. 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.
5. The sum and average are printed to the console using the printf() function.