if i have two credit cards, one with a balance of 1000$ and 11%
intrest, and another one with a balance of 2500$ and 20$ interest,
which one should i focus on paying off first in order to get out of
debt the fastest?

i know paying off the lesser ballance one first would make me feel
better because i would only have 1 more credit card left, but this may
not be the wise choice in the end, because i may be paying more
interest on the other?

in this scenario, i have 400$ per month to pay on the cards in any order.

It's always better to pay off the highest amount (which, in your case,
also has the highest interest)first. This will make getting out of
debt quicker...so hang on to that thought.

Kriswrite

ok thank you very much, how do i give you a tip?

Mike, no need. I posted a comment, not an answer, so you could apply
the few cents you saved to your bills :)

Kriswrite

Thank you so much!! you are a really nice person! have a really super great day!

Call credit card 1 (11%) and see if they will allow you to transfer
the balance from credit card 2 (20%).  By doing that you will save
appro. $225.00.  If this works then tear up credit card 2.

Mathematically, kriswrite-ga is correct.  However as you mentioned,
many people find it encouraging to see progress faster by paying off
the smallest debt while paying only the minimum on the larger, then
applying the full amount to the larger.  If you apply $400/month to
these debts, it really won't matter much either way you do it, as you
will be done paying them both off in about 10 months.  By my rough
calculations (I don't know your minimum payments, etc.), you're
talking less than a few dollars difference.

OOPS!  Bad math!  It's actually about $50 different...

Although the final answer is the same in this case, Kriswrite's method
is incorrect.  You want to pay off the higher INTEREST card first (not
the higher amount).

So as Kris said, pay off the $2500 card first.  

Just4Fun made a good comment too.  If you can transfer the higher
interest balance to the lower interest card you will save a couple
hundred dollars.

Also, if you don't use the cards during the time you're paying them
off then you'll be out of debt much faster.  If having the cards is a
temptation to use them unnecessarilly then you should cut them up.

thank you very much all of you for taking time out of your day to
answer my question! i greatly apreciate it!

You should list all of your debts from smallest to largest and start
paying off the smallest.  After it's paid off use that money plus the
minimum you we putting down on your next smallest debt.  It called the
debt snowball.  Keep it going and pay off your student loans, cars,
and so on.  Worked for me.

Get Dave Ramsey's book the "Total Money Makeover" for the details of
why this makes sense.  Your library probably has it.
http://www.daveramsey.com

Just be sure not to be late on payments on either card so you don't
pay late fees on top of the interest.

Here's an article that you may find helpful:

http://www.bankrate.com/brm/news/cc/19980713.asp

Sincerely,
Boquinha-ga