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Python

Posted by Steven Bell
Steven Bell
660 Points

Balance and Interest

An online bank wants you to create a program that shows prospective customers how their deposits will grow. Your program should read the initial balance and the annual interest rate. Interest is compounded monthly. Print out the balances after the first three months. How should this Python code look?

Python Beginner

1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

This is one way of doing it:

percent_rate = int(input("Enter the percnet interest rate: ").strip())
decimal_rate = percent_rate / 100
initial_balance = int(input("Enter the initial balance: ").strip())

def calculate_balance(month):
    return initial_balance * ((1 + decimal_rate / 12) ** month)

for month in range(1, 4):
    print("The balance at the end of month {} is: {}".format(month, calculate_balance(month)))

I tested the numbers quickly with 100% interest rate and an initial balance of $1.00, since they make the calculations easy, and I think I got the right numbers.