Write a C program to input principle (amount), time and rate (P, T, R) and find Compound Interest. How to calculate compound interest in C programming. Logic to calculate compound interest in C program.

**Example**

**Input**

Enter principle (amount): 1200 Enter time: 2 Enter rate: 5.4

**Output**

Compound Interest = 1333.099243

## Required knowledge

Arithmetic operators, Operator precedence and associativity, Data types, Basic input/output

## Compound Interest formula

Formula to calculate compound interest annually is given by.

Where,

`P` is principle amount

`R` is the rate and

`T` is the time span

## Logic to calculate compound interest

Step by step descriptive logic to find compound interest.

- Input principle amount. Store it in some variable say
`principle`. - Input time in some variable say
`time`. - Input rate in some variable say
`rate`. - Calculate compound interest using formula,
`CI = principle * pow((1 + rate / 100), time)`

. - Finally, print the resultant value of
`CI`.

Read more – Program to find power of a number

## Program to calculate compound interest

```
/**
* C program to calculate Compound Interest
*/
#include <stdio.h>
#include <math.h>
int main()
{
float principle, rate, time, CI;
/* Input principle, time and rate */
printf("Enter principle (amount): ");
scanf("%f", &principle);
printf("Enter time: ");
scanf("%f", &time);
printf("Enter rate: ");
scanf("%f", &rate);
/* Calculate compound interest */
CI = principle* (pow((1 + rate / 100), time));
/* Print the resultant CI */
printf("Compound Interest = %f", CI);
return 0;
}
```

Output

Enter principle (amount): 1200 Enter time: 2 Enter rate: 5.4 Compound Interest = 1333.099243

Happy coding 😉