Need help - Anuities and past due accounts

[TJ111]

I am looking to write an equation that allows me to set up 6 monthly equal payments on a past due account to bring it current. The closest I've gotten is the PMT equation:
PMT= PV* i*(1+r)^n/((1+r)^n-1)

However this would give 6 equal payments to paying the balance in full instead. This equations deals with interest and late fees assesed monthly. Any help would be greatly appreciated.

 

[Yogi]

Can you create an example with the timeline of payments? Is the late fee a fixed amount paid every month? Right now the given info is pretty vague.

If you give me something like this:
t=1: $500 payment, $0 late fee
t=2: $500 payment, $50 late fee
t=3: $1000 payment, $0 late fee
...
t=6: ...
It becomes much easier to setup the formula.

Also, I am skeptical about PMT= PV* i*(1+r)^n/((1+r)^n-1) since (1+r)^n / ((1+r)^n-1) just reduces to 1+r.

 

[TJ111]

Yogi to explain the best can I will lay out a 3 month time line including all variables.


Variables:

Balance = (Previous Balance - Previous payment + 35 Fee)*1.01825
Total Due= past due + Min due
Past Due = Previous total due - previous payment
Min Due = roundup((Previous Balance - Previous payment + 35 Fee)*.02825)+35

t1: 1000.00 Balance, 308.00 total Due, 250.00 past due, 58.00 Min due
t2: 1053.89 Balance, 373.00 total due, 308.00 past due, 65.00 min due
t3: 1108.76 Balance, 440.00 total due, 373.00 past due, 67.00 min due


the example above depicts a balance over 3 months with no payments made in each month. However, thought the joys of 'guess and check,' I know that 6 equal payments of $101.00 will bring the account current as the total due in month 't6' will be 101.00.

So to sum up the question how do I write the equation to find the value of 101.00*6= month 6 total due = 101.00?

 

[Yogi]

....unless Yogi pulls a miracle !

Your mind is about to be blown...
Have excel solver set (month 6 TotalDue - payment) = 0 by changing the value of payment.

Please tell me that this works for you so I don't have to look at this problem anymore. -_-