Practice exam strategy

Two candidates with the same knowledge can score ten points apart because one of them handles the exam better: reads each question properly, manages time, does not get stuck, and avoids changing right answers to wrong ones. Dmitri, who failed his first Network+ attempt by a handful of points and passed easily the second time, puts it simply: the second time he knew a little more, but mostly he had learned how to sit the exam. This lesson covers that skill: reading questions, eliminating options, handling calculations, pacing, reviewing, and the practical side of exam day.

Read the stem first, and read all of it

The stem is the question part. Read it to the end before looking at the options, and pick out three things: the situation (where you are, what is happening), the constraint (what you may or may not do, what has already happened) and the actual question (what, why, which, first, best, most likely). Exam writers put the key word at the end of the stem more often than not.

Watch for words that change the meaning: NOT, EXCEPT, FIRST, NEXT, BEST, MOST LIKELY, LEAST. A question that asks what a technician should do first wants the safe first step, even if several options are things the technician would eventually do. A question that asks for the most likely cause wants the common cause, not the dramatic one.

Eliminate before you choose

Distractors are written to attract people with partial knowledge, so they often contain a real term used in the wrong place. Before choosing, strike out options that are clearly wrong. Common patterns of wrong options:

• Unsafe or outside the technician's role: operating switchgear, bypassing an interlock, skipping lockout.
• Absolute words where the truth is conditional: always, never, all, none. These are sometimes right in safety rules, so read carefully.
• A correct fact that does not answer the question asked.
• Two options that say the same thing in different words; if both cannot be right, neither probably is.
• A plausible term from the wrong system: a static bypass where the question is about generators, or a CRAC where the question is about chilled water.

Even if you cannot find the right answer, eliminating two options turns a one-in-four guess into a one-in-two guess. Over a 40-question exam that matters.

Calculations

Facility exams include short calculations: kW to BTU/h and tons, three-phase current, airflow from heat and ΔT, UPS runtime, PUE, availability, RAID capacity, loss budgets. Do them on the whiteboard or scratch paper you are given, write the formula first, keep units in every line, and check the answer for sense. A three-phase current of 9,000 A for a single rack, or a PUE below 1, is a sign of a slip.

Many calculation questions put the most common wrong answers in the options: the answer without √3, the answer in BTU/h when the question asked for tons, the answer for RAID 5 when the question said RAID 6. If your first answer matches an option instantly, it is still worth one second to check which mistake each other option represents.

Some candidates write this table on their scratch paper in the first two minutes, from memory, so they never have to recall a formula under pressure. Check the exam's rules first; most allow it once the exam has started.

Pacing

Work out your time per question before exam day. The CDCP's 40 questions in 60 minutes give 90 seconds each. A 90-question exam in 90 minutes gives 60 seconds each, minus time for any performance-based items. Plan two passes: a first pass answering everything you can in about 75 percent of the time, flagging questions you are unsure of, and a second pass on the flagged ones. Never leave a question blank on an exam with no penalty for wrong answers; guess and flag it.

# Pacing plan: time per question, checkpoints and first-pass target
def pacing(questions, minutes, first_pass_share=0.75, pbq=0, pbq_minutes=0):
    mcq = questions - pbq
    mcq_minutes = minutes - pbq_minutes
    per_q = mcq_minutes * 60 / mcq
    first = minutes * first_pass_share
    print(f"{questions} questions in {minutes} min: {per_q:.0f} s per multiple-choice question")
    print(f"  first pass done by minute {first:.0f}, leaving {minutes - first:.0f} min to review")
    for frac in (0.25, 0.5, 0.75):
        q = round(mcq * frac)
        t = pbq_minutes + q * per_q / 60 * first_pass_share / 1.0
        print(f"  checkpoint: question {q + pbq} by about minute {t:.0f}")
pacing(40, 60)
pacing(90, 90, pbq=4, pbq_minutes=16)

40 questions in 60 min: 90 s per multiple-choice question
  first pass done by minute 45, leaving 15 min to review
  checkpoint: question 10 by about minute 11
  checkpoint: question 20 by about minute 22
  checkpoint: question 30 by about minute 34
90 questions in 90 min: 52 s per multiple-choice question
  first pass done by minute 68, leaving 22 min to review
  checkpoint: question 26 by about minute 30
  checkpoint: question 47 by about minute 44
  checkpoint: question 68 by about minute 57

The second example allows 16 minutes for four performance-based items. Many candidates skip performance-based items at the start, answer the multiple-choice questions, and come back to them, because a slow simulation at the start can wreck the whole exam's pacing. Check whether your exam lets you move back and forth before planning this.

Reviewing and changing answers

On the second pass, look only at flagged questions first, then at any others if time remains. Change an answer only if you find a definite reason: you misread the stem, you made an arithmetic slip, or a later question reminded you of a fact. Changing on a vague feeling tends to turn right answers into wrong ones.

The practice exam routine

Practice exams are only useful if they are treated like the real thing and then studied afterwards. Jamal's routine for each one:

• Sit it timed, in one go, without notes, at a desk, with the phone in another room.
• Mark it and record the score by topic.
• Go through every question you got wrong and every question you guessed right, and log the reason in one of four categories: did not know, misread the question, calculation slip, or fell for a distractor.
• Make a flashcard for every did-not-know item, and a one-line rule for every misread or distractor (for example: read to the end of the stem before the options).
• Adjust the study plan towards the weakest topics.

The error log is more useful than the score. In his first practice exam Jamal scored 31 of 40, and his log showed that four of his nine errors were misreads, mostly missing NOT and FIRST. Two practice exams later, after drilling stem reading, his misreads were down to one.

Exam day

• Know the rules: identification needed, what you may bring, arrival time, breaks, and for online exams the room and camera rules. Read the candidate handbook a week before.
• For an online proctored exam, test the computer, camera and connection the day before, clear the desk, and close every other program.
• Sleep properly the night before; avoid working a night shift before the exam. Dmitri swapped his shifts with Jamal's so Jamal had two days off before the exam.
• Eat beforehand and arrive early; rushing raises stress and lowers recall.
• If you feel panic, stop for a few slow breaths, then answer an easy question to get moving again.

Exam traps in strategy

• FIRST and NEXT questions want the safe step, usually communicate, protect people, or follow the procedure.
• The most dramatic option is rarely the most likely cause.
• An option that would be right on a different site or with a different role is still wrong for the question as written.
• Do not import facts from your own site that the question has not given; answer from the stem.

Worked elimination

Calculation distractors

Long scenario questions

Some questions give a paragraph of detail, and not all of it matters. Read the question line first, at the end of the stem, then read the scenario looking for the facts that answer it. A long description of a hall's layout followed by a question about who approves a change needs only the risk score and the approval table; the layout is there to test whether you can ignore it. Underline or note the two or three facts that matter on your scratch paper.

When a question uses a term you do not recognize, do not panic. Often the term is a distractor or a brand-specific name, and the question can be answered from the other details. If you can reason out what the term probably means from its parts, such as a pre-action valve being something that acts before water flows, do so, and move on.

The arithmetic of guessing

On an exam with no penalty for wrong answers, a blind guess on a four-option question has a one-in-four chance. If you can eliminate one option, your chance becomes one in three; eliminating two makes it one in two. Suppose you are truly unsure of eight questions on a 40-question exam. Guessing blindly on all eight gives an expected two correct; eliminating two options on each gives an expected four. Two extra marks on the CDCP is five percent, often the difference between a narrow fail and a pass.

# Expected marks from guessing, with and without elimination
unsure = 8
for left in (4, 3, 2):
    expected = unsure / left
    print(f"{left} options left on each of {unsure} questions: expect {expected:.1f} correct")

4 options left on each of 8 questions: expect 2.0 correct
3 options left on each of 8 questions: expect 2.7 correct
2 options left on each of 8 questions: expect 4.0 correct

Performance-based items

Some exams include performance-based items: ordering the steps of a procedure, matching terms to definitions, dragging components onto a diagram, or working in a simulated interface. These often carry more marks than a single multiple-choice question and take longer. Read the instructions on each one carefully, because some allow partial credit and some do not. If your exam lets you move back and forth, it can make sense to note them, answer the multiple-choice questions first, and return with a known amount of time left. Try the item types with the exam provider's own sample items if they publish any.

When a question seems wrong

Occasionally a question looks wrong: two options seem correct, or none does. Choose the option that best fits the exam's body of knowledge rather than your own site's practice, flag it, and use the comment feature if the exam has one. Then let it go. Spending five minutes arguing with one question costs more marks than the question is worth.