balance = 320000
annualInterestRate = 0.2
monthlyInterestRate = annualInterestRate/12
epsilon = 0.01
low = balance/12
high = (balance(1 + monthlyInterestRate)**12)/12
pay = (low + high)/2.0
while (pay - balance)>= epsilon:
print('low ' + str(low) + 'high ' + str(high) + 'pay ' + str(pay))
if(pay < balance):
low = pay
else:
high = pay
pay = (high + low)/2.0
print 'Low Payment: ' + pay
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