OCW 6-00 sc. PS1 (Decimal option)

from decimal import *               # Decimal module
getcontext().prec = 28

balance = float(raw_input('Enter the outstanding balance on the credit card: '))
balanceStr = float(0)               #Decimal module can't work with floats, needs to convert to string

annualRate = float(raw_input('Enter the annual interest rate on the credit card: '))

minPaymentRate = float(raw_input('Enter the minimum monthly payment rate on the credit card: '))


print("\n")

monthly_rate = annualRate/12

print("\n")

months = int(0)
minMonPay = float (0)           #minimum monthly pay
minMonPayStr = float (0)
intsPaid = float (0)            #interests paid
principalPaid = float(0)
principalPaidStr = float(0)
totalAmountPaid = float(0)
totalAmountPaidStr = float(0)


while months<12:
    months = months+1
    print 'month:', months

    minMonPay = (minPaymentRate * balance)
    minMonPayStr = str(minMonPay)
    print 'minimum monthly payment:', '$', Decimal (minMonPayStr).quantize(Decimal('0.01'), rounding=ROUND_UP)

    intsPaid = monthly_rate * balance
    principalPaid = minMonPay - intsPaid
    principalPaidStr = str(principalPaid)
    print 'principal Paid', '$', Decimal (principalPaidStr).quantize(Decimal('0.01'), rounding=ROUND_UP)

    balance = (balance - (principalPaid))
    balanceStr = str(balance)
    print 'remaining balance', '$', Decimal (balanceStr).quantize(Decimal('0.01'), rounding=ROUND_UP)

    totalAmountPaid = (totalAmountPaid + minMonPay)

    print("\n")

print "RESULT\n"
print 'remaining balance', '$', Decimal (balanceStr).quantize(Decimal('0.01'), rounding=ROUND_UP)
totalAmountPaidStr = str(totalAmountPaid)
print 'totalAmountPaid', '$', Decimal (totalAmountPaidStr).quantize(Decimal('0.01'), rounding=ROUND_UP)