if over you mean division then it would be 2556 divided by 5000 and that would equal 0.5112 and if you meant it to be addition because sum means the answer of an addition problem then it would be 7556 because of 2556 plus 5000, but i dont know if that is what you meant by your question. if you explain the lesson to me that you are learning, then i might be of more help to you in solving your problem.