On the day of the exam you were as confident as a porcupine with extended twills (imagine that …). You know in your heart you’ve done what you could. You are anxious. You are ready. Then here comes the first question. You think to yourself, “WTF is this? I don’t remember reading about this.” Then the next question was so vague you wondered if it was actually written in English. The third question, seemed like there are two answers instead of one. The fourth was no easier. By the fifth question, all that confidence went down the toilet and by the sixth you are in a near panic.By the time the exam was all over, you are so bewildered that you wonder if someone got the license plate of the truck that hit you. You have no idea if you passed or failed and wondering what you have done wrong and if you actually done enough. I have observed that often times the key reason for a person failing an exam was not because he or she did not know the material, but rather because he or she simply lost focus brought upon by the stress and sometimes panicked over the confusion brought about by how the questions in the exam was framed.

If you’ve gone through a similar painful situation or worried that you may go through the same situation as I have described above when you go take a cert exam, I’d like to share a simple secret that I always take with me whenever I take an exam. It all comes down to simple math.

Let’s look at the PMP exam requirement as an example:

“The PMP® exam is a 4-hour multiple choice exam. In these 4 hours, you are going to have to answer 200 questions. Each question is either scenario based or knowledge based and has 4 possible answers – A, B, C or D. You can only select one answer.

Out of these 200 questions, 25 are considered “pretest questions”. These pretest questions do not affect your score. The PMI uses them as an effective and legitimate way for testing the questions. In other words: new questions for the exam are first tried out in this way, to see how well they work. The pretest questions are randomly placed throughout the exam.

So you start out with 200 questions minus the 25 pretest questions which leaves 175 questions. Out of these, you must answer 106 correctly. That is 61%.” (Source: What is the PMP Exam Passing Score?)

So we know that out of 200 questions only 175 matters and to pass we only need to answer 106 of the 175 correctly. However, there is a wildcard here, we need to factor in the 25 that we have no idea which questions they are. 25 questions that we may all answer correctly, but don’t really count in the score. That would really suck if 1 of the 106 questions that you’ve answered correctly is a pre-test question and therefore your actual score is only 105, which means you fail.

So to negate the pre-test factor, we should set our goal to:  106 + 25 = 131. In other words, to be confident that we actually passed the exam, we will need to have a “buffer” of 25 questions. So in reality the surefire way to pass the exam is to get 65.5% of the 200 questions, vice 61% of the 175 questions. In the grand scheme of things and comparison of probability, it is not really a big jump. We will look at probability in a different context in a little bit. But for now, we’ve established that our passing goal is 65.5%.

Just FYI Formula: 131 / 200 = .655 or 65.5%

We also know that we have 4 hours to complete a 200 question exam. That gives you 1.2 minutes per question. Believe it or not this is actually pretty long. I would recommend targeting to spend only 1 minute maximum per question. This will give an extra 40 minutes to review your answers (that is after you follow the next steps below you still feel like doing a review).

Now that we now know what our passing goal and time/per question ratio is, we are now really prepared to take the exam. Most exams will allow you to have a blank sheet of paper and a pencil to use as a scratch paper. Make sure that you get them. You will need it. Also most cert exams allow you to mark the questions that you would like to go back to for a variety reasons, including, but not limited to:

• You are not sure of your answer
• You don’t know the answer

 As I mentioned there are a variety of reasons why you would want mark an answer, but the two reasons above are the only two that we will concern ourselves about.

This is where the next step of our technique comes in. In your scratch paper, set-up two columns. One column is going to be where you will write the question number of questions that you are not sure of your answer. The other columns is where you will write the question number of the questions that you don’t know the answer.

Third step start answering the questions, keeping in mind your time constraint of 1 minute max per question. You don’t have to distract yourself by really counting every second of the clock. Just have a feel for it and keep it in the back of your mind. Once you run into a question that you are not sure of, pick the one that you think is the best answer. Then write the question number in the appropriate column. Do the same for questions that you don’t know the answer. DO NOT SKIP A QUESTION. Pick an answer and move on. Just make sure you mark that question number.

Once you’ve finished all the questions and stayed true to the self-imposed time constraints (in our case one minute per question), you should have plenty of time for the 4^th step. Count the total number of questions that you were not sure of and count the number of questions that you did not know the answer. If the total number of questions you were not sure of and don’t know the answer to comes out to be less than 69 questions (based on our PMP example), then I would highly recommend: STOP!!! Stop pulling your hair out, you are done.

But just for giggles, let’s assume that it is a little bit more complicated than that. Somehow, you marked even the questions that you have only a slimmer of doubt as to the answer. Continuing with our example the numbers came out as follows:

• Not sure: 60
• Don’t know: 25

Do you start the sweat pumps and start going through each “Not sure” question? I say, hold your horses, mate! Let’s do some math, actually probability to be exact. Let’s throw away, the 25 don’t know. Let us assume, you have the luck of a possum crossing the I-5 Freeway in the middle of rush hour in Los Angeles. Essentially, no way you can get lucky in getting a right on the 25 guesses that you’ve made in the “Don’t know” column.

You have 115 answers that you are pretty sure of. If you go with the 106 mark as originally suggested to be the passing score out of 175 non-pre-test questions, you’ve already passed. But since you’ve set a higher goal of 131 to get a surefire-no-way-you-can-fail score, you need 16 more correct answers. 16 is 27% of 60. With this info, ask yourself this:

1. What are the chances of me missing more than 70% of the questions in the “Not sure” column?
2. What are the chances of 10 or more of the pre-test questions being in the 115 answers that I am pretty sure of?

The answer to question two is actually hard to really know and it is a gamble. However, it is negated by your answer to question one. Question one is really a gut check. It’s not exact math or science, but its all about probability with margins of error. But in the end, you will know the answer to this. So this goes without saying that if the answer to 1 and 2 is “pretty low chance.” Take a deep breath, stretch and submit your answers. In the case of the PMP or other computer-based certs you will immediately know the results. In the case of scantron-based exams such as CISSP, you will not immediately know the results, but you will be confident that there is a very high probability that you’ve passed.

I have used this technique in all the cert exams that I have taken and the results were obviously great. I also used this in taking college exams, although slightly adjusted based on the target score that I want beyond what is required to pass. Obviously, college exams are not simply pass/fail as cert exams, so I have to tweak my goals to ensure that I have the best score possible.

In summary, here are the steps of using math and probability to help you pass the exam:

1. Know your “true” passing goal and time/question ratio
2. Set-up two columns in your scratch paper: “Not sure” and “Don’t know”
3. Answer the questions. Mark columns with question numbers as appropriate. DO NOT SKIP A QUESTION. Even if you don’t know the answer, make your best guess.
4. Do the math, sum up “Not sure” and “Don’t know” and compare with your passing goal.
5. If necessary, do a probability/gut check. How many of the “Not sure” do you think you will miss? Is it pretty high? Or is it low?

All that said, I wish you the best of luck. Yes LUCK does help, but I prefer to understand probability .

Review

Rita’s book is boon to men and women preparing to take PMI’s certification examination. — – J. Davidson Frame, Ph.D., PMP and Past PMI Director of CertificationRita’s book is boon to men and women preparing to take PMI’s certification examination. — J. Davidson Frame, Ph.D., PMP and Past PMI Director of Certification

Can you imagine valuing a book so much that you send the author a “Thank You” letter? Tens of thousands of people understand why (more…)

Learn the latest principles and certification objectives in The PMBOK Guide, Fourth Edition, in a unique and inspiring way with Head First PMP . The second edition of this book helps you prepare for the PMP certification exam using a visually rich format designed for the way your brain works. You’ll find a full-length sample exam included inside the book. More than just proof of passing a test, a PMP certification means that you have the knowledge to solve most common project pr (more…)

Review

Rita’s book is boon to men and women preparing to take PMI’s certification examination. –J. Davidson Frame, Ph.D., PMP and Past PMI Director of Certification

Can you imagine valuing a book so much that you send the author a Thank You letter? Hundreds of thousands of project managers understand why PMP Exam Prep by Rita Mulcahy, PMP, is a worldwide best-seller. Is it Rita’s years of PMP exam preparation experience? The endless hours of ongoing res (more…)