Formula about solving interest

Hello

I need all the help possible, let say if I have a credit card with a balance of $4000 and I get a promotional interest rate of 4% for 24 months but I will only be able to pay $100 per month I want to know in those 24 months even though I will not be able to finish my balance how much do I cut off my balance and how much do I end up paying in interest.

Thanks.

Hi.
Have a look at the attached spreadsheet and see if it is what you are looking for:

Credit Card Calculator.xlsx

All the best

Hi Ursul,

That's a good work book, however I don't think part C is working correctly. It is showing that the amount outstanding is the original amount less the sum of payments, but that doesn't take into account the interest that is added each month. ie. If I put $100 in as monthly payment, an opening balance of $4000 it's saying that after 24 months the outstanding balance would be $1600 - I get a little over $1800 based upon the payment being made each month before interested is calculated at the end of the month.
credit card.xlsx

Originally Posted by elvla2

let say if I have a credit card with a balance of $4000 and I get a promotional interest rate of 4% for 24 months but I will only be able to pay $100 per month I want to know in those 24 months even though I will not be able to finish my balance how much do I cut off my balance and how much do I end up paying in interest.

For a US loan, the ending balance after 24 months is about $1838.28, calculated as follows:

=FV(4%/12,24,100,-4000)

So the balance is reduced by about $2161.72, calculated as follows:

=4000-FV(4%/12,24,100,-4000)

And the amount of interest is about $238.28, calculated as follows:

=24*100-(4000-FV(4%/12,24,100,-4000))

OK I've corrected my spreadsheet but even using the CUMIPMT formula this assumes the whole $4000 is paid off (so ignore you can ignore it), so the other spreadsheet is more correct but I have made changes to this because the first interest calculation was made on $3900 not $4000, so a few extra cents were added to each payment and thus added to the total.

credit card.xlsx
Credit Card Calculator.xlsx