I think I am missing something important here. I have read most post on here about APR, guides on how to calculate it and official loan rule books.
However sites like wonga, quickquid etc seem to have representative APR's that way exceed any formula I can find. for example..
Borrow £500 for 5 months
Interest payable £367.05
Total amount payable: £867.05 in 5 instalments
5 payments of £173.41
Representative 1297% APR
Interest rate 292% per annum (fixed)
How can I, given the above information only, calculate the same APR? Or is it not something that can be calculated, it is based on statical (historic) data?
How would you solve this?