Find the sum of GP or geometric progression series in the c program; Through this tutorial, we will learn how to find sum of GP series or geometric progression series using formula, for loop and function in c programs.

## Programs to Find Sum of Geometric Progression Series in C

- C Program to Find Sum of Geometric Progression Series using Formula
- C Program to Find Sum of Geometric Progression Series using For Loop
- C Program to Find Sum of Geometric Progression Series using Function

### C Program to Find Sum of Geometric Progression Series using Formula

/* C Program to find Sum of Geometric Progression Series */ #include <stdio.h> #include<math.h> int main() { int a, n, r; float tn, sum = 0; printf(" Please Enter First Number of an G.P Series: "); scanf("%d", &a); printf(" Please Enter the Total Numbers in this G.P Series: "); scanf("%d", &n); printf(" Please Enter the Common Ratio: "); scanf("%d", &r); sum = (a * (1 - pow(r, n ))) / (1- r); tn = a * (pow(r, n - 1)); printf("\n The Sum of Geometric Progression Series = %.2f", sum); printf("\n The tn Term of Geometric Progression Series = %.2f \n", tn); return 0; }

The output of the above c program; is as follows:

Please Enter First Number of an G.P Series: 1 Please Enter the Total Numbers in this G.P Series: 5 Please Enter the Common Ratio: 2 The Sum of Geometric Progression Series = 31.00 The tn Term of Geometric Progression Series = 16.00

### C Program to Find Sum of Geometric Progression Series using For Loop

/* C Program to find Sum of Geometric Progression Series */ #include <stdio.h> #include<math.h> int main() { int a, n, r, value, i; float sum = 0; printf(" Please Enter First Number of an G.P Series: "); scanf("%d", &a); printf(" Please Enter the Total Numbers in this G.P Series: "); scanf("%d", &n); printf(" Please Enter the Common Ratio: "); scanf("%d", &r); value = a; printf("G.P Series : "); for(i = 0; i < n; i++) { printf("%d ", value); sum = sum + value; value = value * r; } printf("\n The Sum of Geometric Progression Series = %f\n", sum); return 0; }

The output of the above c program; is as follows:

Please Enter First Number of an G.P Series: 2 Please Enter the Total Numbers in this G.P Series: 5 Please Enter the Common Ratio: 2 G.P Series : 2 4 8 16 32 The Sum of Geometric Progression Series = 62.000000

### C Program to Find Sum of Geometric Progression Series using Function

/* C Program to find Sum of Geometric Progression Series */ #include <stdio.h> #include<math.h> int sumofGP(int a, int n, int r) { int sum = (a * (1 - pow(r, n))) / (1- r); return sum; } int main() { int a, n, r; float sum = 0; printf(" Please Enter First Number of an G.P Series: "); scanf("%d", &a); printf(" Please Enter the Total Numbers in this G.P Series: "); scanf("%d", &n); printf(" Please Enter the Common Ratio: "); scanf("%d", &r); sum = sumofGP(a, n, r); printf("\n The Sum of Geometric Progression Series = %f\n", sum); return 0; }

The output of the above c program; is as follows:

Please Enter First Number of an G.P Series: 2 Please Enter the Total Numbers in this G.P Series: 5 Please Enter the Common Ratio: 2 The Sum of Geometric Progression Series = 62.000000