Thread: interest problem

How much interest would you have to pay for a credit card balance of 644.00 that is 9 months overdue, if a 22% annual rate is charge.

Is this a future value question or what formula should I be using here.

FV = PMT( (1 + i)^n -1 )/i

I found it. So simple, yet so difficult -math.

I = Prt

I = 644(.22)(.75)
I = 106.26

the formula you have used is for simple interest (as opposed to compound interest). Was that intentional?