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Dear John,
I'm struggling to understand the example for compound interest deception.
If the guy borrows 2000 sterling and has to pay back 2100 then annual interest rate is surely 5%.
Where is the 9% coming from? You use expression "true interest rate", am I missing the point?
I'm sorry if this is a bit blunt, I just like maths and to understand it, hence the challenge with deception for compound interest. Matt