# Interest Rate Calculations - I believe compounding

Question asked by hjvanes on Feb 18, 2014
Latest reply on Feb 19, 2014 by mikebeargie

Dear FM PPL,

I have attempted this but am not quite sure how I am meant to get the results to achieve a proper amount.

A simple Interst calculation after it becomes due is pretty easy as a once off. Ie..total amount 100 and payable within 30 days. After 30 days interest would kick in for say 10% per annum.

However it hit me in the head that this will not cater for part payment in which case interest will keep running after the 30 days on that which is still outstanding.

So \$100.

part payment with 30 days of \$50

on day 31 outstanding is \$50

Penatlty interest per annum after 30 days is 10% = => \$50+\$5 = \$55 ourtstanding

part payment \$25 on outstanding of \$55 => 55 - 25 = \$30

after 60 days 10% should be applied to \$30 dollars = \$3

full payment of \$33 finally received

Total accumulated pay is 100+5+3 = \$108

The calculation I am trying to obtain is one for calculation of interest after so many days overdue on outstanding amount but more importantly on accumulated total amount paid.

Any help would be greatly appreciate and thank you in advance.

regards,

HJ