the interest rate if 15% per year.
the interest is compounded monthly.
the monthly interest rate is 15/12 = 1.25%.
the payment at the end of each month is equal to 200.
you would more then likely need to use a financial calculator to solve this.
the financial calculator i used is the TI-BA-II.
inputs are:
present value = 5000
future value = 0
interest rate per month = 15%/12 = 1.25%
payments at the end of each month = -200
i then had the calculator tell me that the number of months is equal to 30.16243479.
i then multiplied 200 by that to get a sum of all payments equal to 6032.486959.
i then subtracted 5000 from that to get 1032.486959.
that's the total interest paid, which i presume you mean is the sum of all interest payments.
you can do the same thing with an online calculator.
it makes the same calculations, except it provides results rounded to the nearest payment.
this may alter the results slightly as you will see.
here are the inputs:
here are the results:
the result is that the number of months is 30.16
multiply 200 by 30.16 and you get total finance charge of 6032.
subtract 5000 from that to get total interest charge of 1032.
my more detailed answer above was a total interest charge of 1032.486959
there is a difference due to rounding error, but it's quite small.
the online financial tool i used can be found at https://arachnoid.com/finance/
you can also use the financial formulas in microsoft excel.
the use of that gave me the following result:
n = 30.16243479
that agreed with what the TI-BA-II gave me for the number of months.
if you don't have the TI-BA-II calculator, or a copy of microsoft excel, then use the results that the online financial calculator gives you.
that would be a number of months of 30.16 with a total financial charge of 6032 which results in a total interest charge of 1032.