C Exercises: Find the Sum of GP series

Last update on March 18 2025 13:35:25 (UTC/GMT +8 hours)

52. Sum of G.P. Series

Write a C program to find the sum of the G.P. series.

This C program calculates the sum of a geometric progression (G.P.) series. It takes the first term (g1), common ratio (cr), and the number of terms (ntrm) as input. Then, it iterates through each term, calculates the G.P. term using the formula, adds it to the sum, and prints each term. Finally, it prints the sum of the G.P. series.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>  // Include the standard input/output header file. 
#include <math.h>   // Include the math header file.

void main(){

float g1,cr,i,n,j;
float ntrm,gpn;
float sum=0;

  // Get input for first term, number of terms and common ratio
printf("\\n\\n Find the Sum of GP series.:\\n ");
printf("-------------------------\\n");
printf("Input the first number of the G.P. series: ");
scanf("%f",&g1);
printf("Input the number or terms in the G.P. series: ");
scanf("%f",&ntrm);
printf("Input the common ratio of G.P. series: ");
scanf("%f",&cr);

  // Generate G.P. series 
printf("\\nThe numbers for the G.P. series:\\n ");
printf("%f ",g1);
sum=g1;

  // Calculate and print G.P. terms 
for(j=1;j<ntrm;j++){
gpn=g1*pow(cr,j);
sum=sum+gpn;
printf("%f ",gpn);
  }

  // Print sum of G.P. series
printf("\\nThe Sum of the G.P. series : %f\\n\\n",sum);

}

Output:

Input the first number of the G.P. series: 3                                                                  
Input the number or terms in the G.P. series: 5                                                               
Input the common ratio of G.P. series: 2                                                                      
                                                                                                              
The numbers for the G.P. series:                                                                              
 3.000000 6.000000  12.000000  24.000000  48.000000                                                           
The Sum of the G.P. series : 93.000000

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to calculate the sum of a geometric progression series using the closed-form formula.
Write a C program to generate the terms of a G.P. series using a loop and then compute their sum.
Write a C program to compute the sum of a G.P. series and then determine the ratio between consecutive terms.
Write a C program to compute the sum of a G.P. series recursively.

C Programming Code Editor:

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