Day 41: Python program to calculate simple interest

 

def calculate_simple_interest(principal, rate, time):

    simple_interest = (principal * rate * time) / 100

    return simple_interest

principal = float(input("Enter the principal amount: "))

rate = float(input("Enter the rate of interest: "))

time = float(input("Enter the time in years: "))

simple_interest = calculate_simple_interest(principal, rate, time)

print(f"The Simple Interest is: {simple_interest}")

#source code --> clcoding.com 

Code Explanation:

Function Definition

def calculate_simple_interest(principal, rate, time):

    simple_interest = (principal * rate * time) / 100

    return simple_interest

def: This keyword is used to define a function.

calculate_simple_interest: The name of the function. It describes its purpose—to calculate simple interest.

Parameters:

principal: The initial amount of money (loan or deposit).

rate: The rate of interest (as a percentage).

time: The time for which the money is borrowed or invested, in years.

Formula for Simple Interest:

Simple Interest = Principal × Rate × Time/100

​

Multiply the principal amount by the rate and time.

Divide the result by 100 to calculate the interest.

return simple_interest: Returns the calculated interest value back to where the function is called.

2. User Input

principal = float(input("Enter the principal amount: "))

rate = float(input("Enter the rate of interest: "))

time = float(input("Enter the time in years: "))

input(): Accepts user input as a string.

float(): Converts the input string into a floating-point number to perform arithmetic operations.

Prompts the user to input:

Principal: The starting loan or deposit amount.

Rate: The interest rate (percentage).

Time: The duration (in years) for which interest is calculated.

Example Input:

Enter the principal amount: 1000  

Enter the rate of interest: 5  

Enter the time in years: 2  

3. Function Call

simple_interest = calculate_simple_interest(principal, rate, time)

The calculate_simple_interest() function is called with the user-provided values for principal, rate, and time.

The calculated interest is stored in the variable simple_interest.

Example Calculation (using input values from above):

Simple Interest =1000×5×2/100 =100

4. Output

print(f"The Simple Interest is: {simple_interest}")

f-string: A formatted string used to print variables within a string.

{simple_interest}: Inserts the calculated interest value into the output message.

Example Output:

The Simple Interest is: 100.0