How does the GMAT work?
The questions are delivered using a computer-adaptive format. The questions are dynamically selected in the quantitative and verbal sections. Each test will be unique and the questions will adapt in severity to the ability level that you are showing. In each section there is a large pool of possible questions which range from a low level to a high level of difficulty. The first question in the relevant section will be of moderate difficulty. Should you get that question right, you will be given a harder question. If you get the question wrong, you will be given an easier question. When you finish the section the computer will have as accurate an assessment of your ability level in that area as a computer can probably get.
Only one question is presented at a time, and the computer scores the question before it selects the next one. Due to this, you cannot skip a question, you cannot return to a question and you cannot change the response that you gave to a previous question.
Should you make a mistake and answer a question incorrectly, or if you make a wild random guess and answer a question correctly, then the answers that you give to subsequent questions will enable the computer to put you back onto questions appropriate to your difficulty level. But our advice to you is not to take random guesses. The reason for this is that random guessing can lower your scores quite significantly. Should you not know the answer to a particular question, you should aim to eliminate as many choices as you can then pick the answer that you think is the best one.
Your score in the GMAT is determined by the amount of questions that you answer, whether you managed to answer the questions correctly or not and the level of difficulty of the questions, plus other statistical characteristics of the questions. All of the questions are weighted in accordance with their difficulty and some other statistical properties, they are not weighted according to their test position.
Not all questions actually count towards your final GMAT score, each of the tests contain some questions that are used for pretesting some GMAT questions before they are used in a real examination. You will not know which ones are these questions, they could be anywhere in the test. Therefore, you need to do your very best on all of your questions since you won't know which ones are real and which ones aren't counted when your test is scored.
You do not need great computer skills to take the GMAT, you just need to be able to use a mouse, and a word processor.