Negative Marking: When Should You Guess in an MCQ Test?
The simple maths behind −0.25 negative marking, when an educated guess helps your score, and when leaving a question blank is the smarter choice.
By the World MCQ Forum Editorial Team · 27 October 2026 · 3 min read
Negative marking makes many candidates nervous, and nervous candidates make one of two mistakes: they either guess wildly on everything or refuse to guess at all. Both cost marks. A few minutes with the actual numbers will tell you exactly what to do.
Many recruitment tests deduct a quarter mark for each wrong answer. For example, FPSC’s published schemes for several 2026 advertisements state “negative marking of 0.25 per wrong answer”. Always check the instructions for your own test, because rules differ between commissions and posts.
The maths of a blind guess
Take a question with four options, one correct, and a penalty of −0.25 for a wrong answer.
If you guess completely at random:
- Chance of being right = 1/4, gaining +1
- Chance of being wrong = 3/4, losing 0.25
Expected marks = (1/4 × 1) − (3/4 × 0.25) = 0.25 − 0.1875 = +0.0625
So even a completely blind guess is very slightly positive on average. But “on average” hides a lot of risk: on any single question you are three times more likely to lose a quarter mark than to gain a full one.
The maths of an educated guess
Now suppose you can confidently rule out one option, leaving three:
Expected marks = (1/3 × 1) − (2/3 × 0.25) = 0.333 − 0.167 = +0.167
Rule out two options, leaving two:
Expected marks = (1/2 × 1) − (1/2 × 0.25) = 0.5 − 0.125 = +0.375
| Options you can eliminate | Remaining choices | Expected marks per guess |
|---|---|---|
| None | 4 | +0.06 |
| One | 3 | +0.17 |
| Two | 2 | +0.38 |
The pattern is clear: every option you can confidently eliminate makes guessing much more worthwhile.
So what should you actually do?
A practical rule that follows from the numbers:
- Can eliminate two options? Always answer.
- Can eliminate one option? Answer it. The expected gain is small but real.
- Know nothing at all? Skipping is reasonable, especially if the paper is long and your time is better spent elsewhere. A pure blind guess adds almost nothing on average.
The word confidently matters. If you “eliminate” an option that was actually correct, the maths falls apart. Only rule out options you genuinely know are wrong.
Why candidates still lose marks to negative marking
In practice, most marks are not lost on blind guesses. They are lost on questions candidates think they know:
- Misreading the question. “Which of the following is NOT…” is the classic trap. Underline negatives in your mind before choosing.
- Changing correct answers. Your first answer, when based on real knowledge, is usually better than a nervous second thought. Change an answer only if you notice a specific mistake.
- Mixing up similar facts. For example, confusing the Lahore Resolution (1940) with the Objectives Resolution (1949). Learning the short explanation behind each fact, not just the fact, protects you here.
Train the skill before the exam
Elimination is a skill, and like any skill it improves with practice. Our mock tests let you switch on −0.25 negative marking so you can see how your guessing habits affect your final score. After each test, look at the questions you guessed: were your eliminations right? Over a few tests you will learn how reliable your instincts are, and that is worth more than any rule of thumb.