CS-A1-Worksheet1

'''
Part 1: Loan

By Mark Wu 3217
'''

def calculateMonthlyPayment(principal, annualInterestRate, duration):
    try:
        r = annualInterestRate / 100 / 12 # r is the monthly interest rate
        n = duration * 12 # n is the total month
        monthlyPayment = (principal * r * (r + 1) ** n) / ((r + 1) ** n - 1)
        return monthlyPayment
    except:
        return 'Error'

# print(calculateMonthlyPayment(1000.0, 4.5, 5))