Video Tutorial illustrating: C Program To Calculation of Simple Interest.

**Header File:**

#include<stdio.h> |

To be able to use **printf **function, we have to include **stdio.h** header file.

**main()**

This is the starting point of C program execution.

since it does not return any value, we write **void main()**

**Declaration of Variables:**

int p, n; float r, si; |

variables **p** and **n** are **integer **type variables i.e., they can hold integer values.

variables **r** and **si** are **float **or **real **type variables i.e., they can hold fractional values.

clrscr(); |

to clear the output screen.

**Initialization of Variables:**

p = 1000; n = 3; r = 8.5; |

Principle p = 1000

n or time or duration = 3

rate of interest r = 8.5

**Formula to calculate simple interest:**

si = ( p * n * r ) / 100; |

The mathematical formula si = ( p x n x r ) / 100; is written as si = ( p * n * r ) / 100;

**Output statement:**

printf("%f\n",si); |

the function **printf **is present inside **stdio.h** header file. **%f** is formatting string for float or real type values.

getch(); |

function to return to the console window.

**Video Tutorial: C Program to calculate Simple Interest **

**Full Source code to calculate simple interest in C program:**

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | #include<stdio.h> void main() { int p, n; float r, si; clrscr(); p = 1000; n = 3; r = 8.5; si = ( p * n * r ) / 100; printf("%f\n",si); getch(); } |

**Output:**

255.000000